EEVblog Electronics Community Forum

Products => Crowd Funded Projects => Topic started by: chriswebb on July 11, 2019, 07:46:27 pm

Title: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: chriswebb on July 11, 2019, 07:46:27 pm
Thought this forum would be interested in the latest product about to launch from the people who did the EEZ H24005 bench power supply:

Quote
The EEZ Bench Box 3 (BB3) represents a new category of modular Test and Measurement (T&M) equipment. It provides a complete hardware and software framework that bridges the gap between – and combines the best features of – DIY hobbyist tools and professional benchtop equipment. BB3 was inspired by the EEZ H24005 power supply, which attracted many enthusiasts with its broad feature set, rich user interface, DIY friendliness, and fully open source design. BB3 will initially ship with modules that provide the same functionality as the H24005, but those modules will be slotted into a device that also delivers improved modularity, enhanced flexibility, greater capacity, and more processing power.

Our campaign will allow backers with different backgrounds, interests, and budgets to configure their BB3 however they like. Get a bare PCB set or add a custom-made enclosure. Add the three core modules, if you like, and you’ll have an Almost-Ready-To-Run (ARTR) bench box into which you can slot one of our power modules. We’re going for maximum flexibility, here.

Link to the crowd supply. (https://www.crowdsupply.com/envox/eez-bb3)

EEVBlog forum launch thread around the H24005 here. (https://www.eevblog.com/forum/crowd-funded-projects/preparing-eez-h24005-for-crowdfunding/)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Kean on July 12, 2019, 01:22:04 am
I have a couple of the H24005, and this new design looks quite good.
Ethernet connection should be on the rear panel IMHO.
Maybe they'll make an SMU plug-in - that would be cool.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Rerouter on July 12, 2019, 01:29:48 am
Kean. If you have thoughts on how your would implement an SMU plugin. I'm willing to lay it out. Been working piecemeal on making a 4 quadrant output stage but I am limited in knowledge as far as making it accurate enough for SMU level use cases.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Kean on July 12, 2019, 04:27:01 am
Kean. If you have thoughts on how your would implement an SMU plugin. I'm willing to lay it out. Been working piecemeal on making a 4 quadrant output stage but I am limited in knowledge as far as making it accurate enough for SMU level use cases.

Not really.  I had dabbled with a design, but the precision I was aiming at was quite low.
I'm not expecting anything like the performance of a Keithley 2400 of course, but something 4 quadrant and uA or better resolution.

There is the EasySMU reference design/evalutation board from AD, but it is somewhat limited with only ±12V/±40mA
Still many occasions I think I'd find that useful.  Of course, there is no stock anywhere of the required eval board.
https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/dc2591a.html#eb-overview (https://www.analog.com/en/design-center/evaluation-hardware-and-software/evaluation-boards-kits/dc2591a.html#eb-overview)

Marco Reps was working on an open source SMU design called OSMU, but development on that seems to have stalled.  Not sure what his planned specs were.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Rerouter on July 12, 2019, 12:23:10 pm
I would say dream for the keithley, but lets see how we can approach it economically, the main pain for me is I do not know what the input structure looks like on a SMU, I assume it is similar to an electometer but with higher bandwidth for most of the ranges, equally what voltage and current ranges are you expecting?

So we have this, the keithely 2400 output stage, nothing hard or expensive to make, and can be made a lot more flexible by using switching preregulation to reduce the total power dissipation of the output stage, instead of using all those taps, just keep it working like a bootstrap supply to keep the op amp under low power while leaving headroom for the maximum bandwidth of the transient response
[attach=2]

Watching Dave's teardown, things of note:
5.5 digit 1uA range at the low end, for measureing, while having a 10nA output resolution so, what can we do to get close to that, e.g. maybe we have a 12-16 bit 1uA full scale range, its not impossible, just needs good layout and decent op amps. (ENOB means we probably end up closer to 3-4 digits)

The keithley does use a switching supply to make its +-225V rails, we could just do it a little more modern. tracking instead of fixed for higher output wattage

E.g. they use an AD847JN for the output op amp, in many ways that is a fairly rubbish op amp compared to what is available today. High bias currents, high offset voltage, only really has speed and gain going for it.

The ADC converter is a multi-slope converter controlled by an FPGA, now from another thread on this forum, the base of operation and op amps required for solid operation does not seem expensive, getting it to play nice over multiple decades of input may be harder, and this is where I would currently struggle, As I would probably be more willing to throw it at a self contained ADC chip, and focus on an analog control loop and managing gain with op amps.

I suppose the multislope does gain you an integrator stage, the easier way to do device power measurement would be to measure the integrator voltage set to a suitable range to get the mA from the integrated mAh allowing the measurement that so many EE's seem to struggle with when devices have uA sleep currents mixed in with mA active currents. just at X samples per second sum to bring the integrator to 0V and measure the charge to cancel, this will give you a wide range device power consuption.

Again throw some thoughts out, the man behind this project is very good at switching converters, so we may just need to step in to guide the linear and measurement side.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on July 12, 2019, 09:52:05 pm
Oh, it seems that party started here without me :). Thanks @chriswebb for opening this topic and others for followed up.

Ethernet connection should be on the rear panel IMHO.

Yeah, it's not simple at all to keep wire harness (check here (https://www.envox.hr/eez/eez-bench-box-3/eez-bb3-wire-harness.html)) to lowest possible level, minimize PCB dimensions (especially the MCU board that has 4-layers) and have all things on the right places. I was thinking a lot, what to do, and for start I'm very satisfied with minimizing AC wiring (and soldering) to the minimum: currently only AC cables are what connect AUX-PS board (where soft-start/standby control is placed) and AC/DC power modules.
Also I'm strongly believe that Ethernet (e.g. wired connection) should be an integral part of such kind of equipment, and that is better to have it on front panel then to remove it completely or replace with wireless. One can argue that we already have (wired) USB, but we have more ambitious plans for it that I believe will be soon in position to present.

Maybe they'll make an SMU plug-in - that would be cool.

Right, and as the first step in that direction I'd like to build a bidirectional 2-quadrant power module. Then support for all four should follows naturally, and of course we have to expand existing software/firmware that decent SMU functionality would be possible.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Teichhermelin on July 14, 2019, 10:28:36 am
Nice Idea
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Zucca on July 15, 2019, 12:15:19 pm
Subbed. I keep my eyes on you. The modularity is a must  :-+ .

Some SMU homework to read for inspiration, K2400:

https://www.eevblog.com/forum/testgear/keithley-2400-sourcemeter-review-and-teardown/ (https://www.eevblog.com/forum/testgear/keithley-2400-sourcemeter-review-and-teardown/)
https://dev.xdevs.com/projects/kei2400/repository/raw/service/Keithley%202400%20Service%20Manual.pdf (https://dev.xdevs.com/projects/kei2400/repository/raw/service/Keithley%202400%20Service%20Manual.pdf)

Last week I was just talking with a Keysight Engineer regarding the N6700 SMU Module

1) The burden voltage for the current measurement is almost 0V
2) The current range switch very fast without losing any data, AKA "Glitch free" (it can analyze the power spike if a device goes out from sleep mode).

It seems there is a lot of demanding right now regarding a DC power supply which can assit the design of low power eg. IoT devices.

I would more than happy to see a module to have not more than 20W of power but can do something like (best case of course!):

Quote
Voltage, 20 V range: 0.025% + 1.8 mV
Voltage, 6 V range: 0.025% + 600 µV
Current, 3 A and 1 A ranges: 0.04% + 300 µA
Current, 10 mA range: 0.25% + 5 µA

Here also the feature to simulate a Li-Ion battery could be handy (it could be just software jazz.....)

I can only suggest to have in mind the low power design process.

PS: Also a 100W DC electric load module would be fantastic, with some feature to analyse battery discharge process.

Now back to work, I have something to finish up.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on July 15, 2019, 12:24:28 pm
2) The current range switch very fast without losing any data, AKA "Glitch free" (it can analyze the power spike if a device goes out from sleep mode).

I'd like to learn how "very fast" is really fast: do we talk about something in a range of microseconds, tens, hundreds (or more) microseconds?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Zucca on July 15, 2019, 01:31:32 pm
I'd like to learn how "very fast" is really fast: do we talk about something in a range of microseconds, tens, hundreds (or more) microseconds?

I asked the very same question. He told me something like:"The two current ranges are always on, you don't switch from one to the other, you just switch what you display"  :-//
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: exe on July 15, 2019, 02:15:34 pm
I asked the very same question. He told me something like:"The two current ranges are always on, you don't switch from one to the other, you just switch what you display"  :-//

To me it sounds like there are two power supplies in parallel, the lower range has slightly higher voltage. When a current spike occurs, the first power supply saturates and drops voltage (CC mode), then second starts working. But that's just a guess :)

Something like this: https://www.keysight.com/main/editorial.jspx?cc=US&lc=eng&ckey=520808&nid=-11143.0.00&id=520808 (https://www.keysight.com/main/editorial.jspx?cc=US&lc=eng&ckey=520808&nid=-11143.0.00&id=520808) ("Learn to connect power supplies in parallel for higher current output").

UP: relevant video: https://www.youtube.com/watch?v=qaQa60WRDfQ (https://www.youtube.com/watch?v=qaQa60WRDfQ)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on July 15, 2019, 02:55:00 pm
Hm, that makes more sense the using multiple resistor's based current sense :). If current sense resistors are used you have to switch in one moment of time from one to another, or in case of just two ranges you can bypass low-range (high resistance) shunt with MOSFET switch that is connected in series with hi-range shunt. Switching speed is finite, it could be in a range of microseconds or perhaps less, but still more then zero.

So, the existing H24005 and new BB3 (with two DCP405 power modules inserted into slot #1 and #2) can be under firmware control coupled in parallel (using internal power relay!) and it should be possible to add in firmware such "auto-ranging" mode of operation that user don't need to think a lot about settings, and proper measurement will be presented on the screen (or send to PC).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Zucca on July 17, 2019, 01:46:28 pm
how funny

https://www.eevblog.com/forum/testgear/iot-power-profiler-and-battery-life-estimation/msg2553039/#msg2553039 (https://www.eevblog.com/forum/testgear/iot-power-profiler-and-battery-life-estimation/msg2553039/#msg2553039)
Title: EEZ Bench Box 3 new HMI
Post by: prasimix on August 24, 2019, 12:44:56 pm
A brief preview of new user interface on 4.3" TFT touchscreen display driven directly by STM32F7 and created using open source EEZ Studio:

https://www.youtube.com/watch?v=jcws6NiOT-s (https://www.youtube.com/watch?v=jcws6NiOT-s)
Title: Cardboard boxes are ready
Post by: prasimix on September 11, 2019, 07:25:25 am
I've received yesterday small batch of cardboard transportation boxes for BB3 kit:

(http://i.imgur.com/E1IuF3U.jpg) (https://imgur.com/E1IuF3U)

... when assembled it looks like this:

(https://i.imgur.com/KzjwJsb.jpg)

Additional small box is used for packaging three basic modules:

(http://i.imgur.com/6H1UsPi.jpg) (https://imgur.com/6H1UsPi)

Everything packaged: peripheral modules with AC/DC power modules come in the middle, small box with basic modules goes below. The main box has additional envelope for improved strength and for easier handling with all parts inside the box:

(http://i.imgur.com/3DD1gbt.jpg) (https://imgur.com/3DD1gbt)


Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Rerouter on September 11, 2019, 07:49:54 am
 Now just waiting to buy one of these,

Any ballpark on what a box and 3x 405's would run?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on September 11, 2019, 08:28:55 am
We're trying to provide a 2-channel version (2 x DCP405B) in a same price range as previously backed H24005 at least for the early birds (all who are subscribed to the campaign will receive notice about exact start time in advance). 
Ok, the question is what is more interesting for the users: DCP405 or DCP405B model? The same PCB will be used for both, but the later comes without the following features:
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Rerouter on September 11, 2019, 08:31:21 am
I'm after the DCP405's
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on September 11, 2019, 08:33:14 am
I'm after the DCP405's

Yeah, it's a "Full Monty", but more costly.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: exe on September 11, 2019, 11:10:40 am
How useful is downprogrammer? Do you have any oscillograms?

Is it going to be a kit, or pre-assembled device? Do I need to solder anything? I like soldering :).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on September 11, 2019, 11:25:30 am
How useful is downprogrammer? Do you have any oscillograms?

Yes, we have: https://www.envox.hr/eez/eez-bench-box-3/eez-bb3-measurements/dcp405-power-module.html#dcp405_dp (https://www.envox.hr/eez/eez-bench-box-3/eez-bb3-measurements/dcp405-power-module.html#dcp405_dp)
Usually people are not aware of such thing, but I hold from the very beginning that is an important ingredient. It does not just discharge Cout (that is very small in our case) but also Cin of the connected devices when set voltage goes down or OE (output enable) is switched off.

Is it going to be a kit, or pre-assembled device? Do I need to solder anything? I like soldering :).

It will be an ARTR (almost ready to run) kit as the previous project. Therefore, you'll need just a Philips screwdriver and about an hour or your work following assembly instructions (as an example you can check here (https://www.envox.hr/eez/bench-power-supply/group-buy-kit-assembly.html) how it looks like for the previous project). Initial firmware version will be also included.
Makers who like soldering, can choose a set of bare PCBs and custom enclosure. Also, you can buy DCP405B module and populate it missing parts to get DCP405 since BOM is published on the GitHub. Perhaps another possibility is that you pledge only the entry level unit that comes with assembled and tested three main modules (i.e. AUX power, MCU module and BP3C backplane) and try to assembly power modules manually.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on September 11, 2019, 11:28:20 am
Oops, the link published above to the measurements include just picture of the output without down-programmer (don't know when the other one disappeared) :palm:
Give me a moment to refresh that page...

EDIT: Ok, Fig. 17 is now added. Feel free to check also Fig. 4 when huge capacitive load is connected on the output: it needs about 20 ms to discharge 2200 μF charged on 30 V.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Rerouter on September 11, 2019, 11:40:55 am
Down-programming makes the output behave like a 1.5 quadrant output, able to source or sink current, (much weaker sinking, and unsure if current limited while sinking)

when you have 2 outputs that can source or sink independently, suddenly you have a poor mans Source-Measure Unit, Its still not as nice as the real thing, but it gets you to a point where you can start recording meaningful data.

Also lets you do weird things like using it for a low burden voltage milliammeter with other devices,

 :palm: I am far to used to bodging things in weird ways....
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: exe on September 11, 2019, 11:53:44 am
If it can sink current, and I can set how much current it sinks, then I'd really want to have it.

What's the sinking capability?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on September 11, 2019, 12:30:54 pm
The sink capability can be calculated using the following equation: Isink, max = (VZD2 - Vth[Q5]) / R30 (See schematics here (https://github.com/eez-open/modular-psu/tree/master/dcp405), Sheet 3of6). Therefore for the current setup, and if we use as average Q5's Vth of 3 V it is (9.1 - 3) / 2.2 = 2.78 A. This is a huge current, but it last in milliseconds (previous down-programmer offered about 0.3 A).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on September 12, 2019, 10:12:05 am
Hi, I still cannot talk about prices. The customized box (i.e. drilled, painted and printed) with mounting frames for TFT display and AC/DC power modules with bare PCBs set will be available during and after the campaign. Anyway, I can say that it will be cheaper then general purpose metal electronic box of the same size that will requires customized front panel, etc.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on October 08, 2019, 11:23:33 pm
To answer Prasimix's previous question, I'll go the full Monty too (most capable modules) AND be watching for new module releases too.
Title: Test batch of enclosures
Post by: prasimix on October 10, 2019, 05:36:56 pm
Today arrived test batch of enclosures, a step closer to the start of crowdfunding campaign. Now it is in final color RAL5022 as in previous project (H24005), but with mat instead of glossy finish:

(https://i.imgur.com/1UCIaE2.jpg)

(https://i.imgur.com/2N6HBu7.jpg)

(https://i.imgur.com/gJzhX1U.jpg)

(https://i.imgur.com/jjajeap.jpg)

(https://i.imgur.com/FBseoRO.jpg)



Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on October 11, 2019, 01:00:56 am
Look at those feet! I had to put the front of my H24005 on a cigar box - and then I had to learn how to smoke cigars.

Did I say that when I was hit by a lightning strike, the H24005 saved ALL of the other equipment on the bench? Loved it!
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on October 11, 2019, 09:04:50 am
Did I say that when I was hit by a lightning strike, the H24005 saved ALL of the other equipment on the bench? Loved it!

The AUX-PS module of the BB3 is equipped with the same AC input protection as H24005, so in time of trouble if you're luck it can do the job of saving its neighbor equipment, too ;)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on October 12, 2019, 09:15:33 am
A very short presentation of the latest prototype:

https://www.youtube.com/watch?v=YK8WY5szdgk (https://www.youtube.com/watch?v=YK8WY5szdgk)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on October 13, 2019, 11:29:18 pm
I like the way the AC/DC supplies are installed; while novel it makes sense to me. Likewise reserving the space for the CPU board.

The new front panel colour will be fine - but how do you intend for users to change over the individual modules? It appears to be a more major task than just undoing a front panel thumb screw and sliding in and out various function modules.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on October 14, 2019, 06:14:32 am
The new front panel colour will be fine - but how do you intend for users to change over the individual modules? It appears to be a more major task than just undoing a front panel thumb screw and sliding in and out various function modules.

The modules are changed in the similar way as in a PC: when top cover is removed (4 screws) to move module one have to remove two screws on the module's front panel (PC modules are fixed with just one screw). Does it make sense?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on October 14, 2019, 07:50:32 pm
It does. I'm looking forward to it.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Black Phoenix on October 24, 2019, 05:03:03 am
Well I like the design, I like the form factor and the modularity. I will wait to see how much it will cost me.

Other question (it may be stupid but please listen to me): Is the firmware able to accept commands? Like for example I develop a small numpad/macropad with a dial. Can I connect via USB-C and use it as an input instead of the touch screen, using the keypad as option selection and for insertion of values?

Something like this:

(https://i.imgur.com/sS3fq1Z.jpg)

(https://i.imgur.com/K4xGewGl.jpg)

(https://preview.redd.it/p36thavi9ln31.jpg?width=960&crop=smart&auto=webp&s=908264e85d173d6267c33b2838665b306cf4630e)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on October 24, 2019, 06:51:39 am
Well Black Phoenix, this is an interesting concept. It sure will reduce the leaning over the test bench to get to the equipment - a big plus. Downside - yet another cable on the bench. Bluetooth connection?

I find the number pad and the two knobs of the Keysight E36200 https://www.keysight.com/en/pc-2993486/200-and-400w-autoranging-bench-power-supply-30-to-120v-10-to-40a?cc=US&lc=eng (https://www.keysight.com/en/pc-2993486/200-and-400w-autoranging-bench-power-supply-30-to-120v-10-to-40a?cc=US&lc=eng) series very useful for getting things done quickly.

An external module, with a number pad and two knobs may be really useful. The same could be said for a lot of other instruments.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on October 24, 2019, 10:46:28 am
Well, what's about speech recognition then? :)

Touch keypad is a key away from any output value (U, I, P) what can be set:

(http://i.imgur.com/Xvec27C.png) (https://imgur.com/Xvec27C)

(http://i.imgur.com/lnKtUYX.png) (https://imgur.com/lnKtUYX)

I suppose that having multiple input devices should simplify and speed up entering desired values. Two encoders on Keysight could serve changing simultaneously two values in case that two hands are used, and if operator have a good bi- or multi-tasking perception. For the rest of the people and situations one hand will be involved anyway, and don't know what is a real advantage.
In our "single hand" case moving from one output value to another is again a single touch operation..., and if encoder is used to set voltage on Ch1, with one touch to e.g. current of Ch2 you can continue to make adjustment with encoder. Additionally, "user sw" can be used to set encoder step (e.g. Auto, 100 mV, 500 mV, 1 V, 2 V or 5 V) that further simplify and speed up settings.

Regarding external keypad: yes, it can be supported in firmware (we have a complete control of it :)): it can be seen as an USB device, or another possibility is to use UART interface that is exposed on the front panel.




Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on October 24, 2019, 09:02:30 pm
I'm not sure speech recognition is a good idea - I swear at my projects so much that any decent supply with be both confused and indignant.  :-DD
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Black Phoenix on October 31, 2019, 01:55:43 pm
Any new update prasimix?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on October 31, 2019, 02:17:00 pm
I'm struggling with finding PCBA service that cost of 2-ch unit is comparable with the previous project (H24005). Hopefully, I'll close a deal with company from Poland in a coming week, but now is completely clear that 450 USD target is not achievable for small production run. OK, BB3 comes with features that goes beyond H24005 and I believe that backers will recognize that.
I still don't have resources (time & money) to pack my baggage and goes to Shenzen what seems is the preferable way if one wants to be sure that everything will run predictably, if not smoothly :).
Perhaps we'll survive with "Made in the EU" manufacturing for a while.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Zucca on November 13, 2019, 03:02:26 pm
I'd like to learn how "very fast" is really fast: do we talk about something in a range of microseconds, tens, hundreds (or more) microseconds?

I asked the very same question. He told me something like:"The two current ranges are always on, you don't switch from one to the other, you just switch what you display"  :-//

Here the Keysight paper for it:

https://literature.cdn.keysight.com/litweb/pdf/5991-0519EN.pdf (https://literature.cdn.keysight.com/litweb/pdf/5991-0519EN.pdf)
Title: Campaign start
Post by: prasimix on November 16, 2019, 08:16:09 am
I'd like to present pledge levels that are set for the campaign:

BB3 enclosureMetal enclosure kit with wire harness and nuts & bolts for three modules, incl. 4.3" TFT touchscreen display, encoder knob and 80 mm fan. Set of bare PCBs for building AUX-PS, MCU STM32F7, BP3C, 2 x DCP405(B) and 1 x DCM220 module. Suitable for builders that have skills, time and patience.
BB3 starterStarter kit includes BB3 enclosure kit without bare PCBs but with assembled AUX-PS, MCU STM32F7 modules and BP3C DIB 3-slot backplane. This pledge represents a starting environment to experimenters that are willing to build their own modules or looking for specific BB3 configuration (e.g. six channels).
BB3 2-ch basic2-ch basic kit includes BB3 starter set, and two DCP405B single channel (40 V, 5 A) basic power modules with AC/DC power modules. A great two channel programmable power source suitable for most of everyday tasks. Expandable to three or four channels.
BB3 2-ch full2-ch full kit includes BB3 starter set, and two DCP405 single channel (40 V, 5 A) fully featured power modules with two AC/DC power modules. A two channel programmable power source with advanced features of remote sensing, remote programming, down-programmer and additional OVP (with crowbar).
BB3 4-ch basic4-ch basic kit includes BB3 starter set, and two DCP405B single channel (40 V, 5 A) basic power modules, one dual channel DCM220 power module and three AC/DC power modules. This is expanded 2-ch basic kit when additional two programmable power sources are needed.
2-ch moduleDCM220, a two channels (2 x 20 V, 4 A) power module with AC/DC power module.
1-ch basic moduleDCP405B, a single channel (40 V, 5 A) basic power module with AC/DC power module.
1-ch full moduleDCP405, a fully featured single channel (40 V, 5 A) power module with remote sensing, remote programming, down-programmer and crowbar OVP. The AC/DC power module is also included.

The campaign should start next week (still cannot get an exact time and date from CS crew).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 16, 2019, 09:05:48 am
For those of you who are familiar with Discord, this is an open invitation to join the discussion group on crowdfunding (#crowdsupply): https://discord.gg/V8gPmws
I will try to answer the questions promptly while I am online, as here.
Title: EEZ Bench Box 3 campaign video
Post by: prasimix on November 18, 2019, 07:29:20 am
This is the official video of the campaign, I believe you will like it no matter what I tried to show a lot in such a short time :)

https://www.youtube.com/watch?v=Uke3_7qHTYk (https://www.youtube.com/watch?v=Uke3_7qHTYk)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on November 18, 2019, 09:42:55 am
Hi prasimix,

if I have understood your pledge levels correctly, there is no complete kit version available? The first tier is mostly the mechanical parts, while the other tiers are fully assembled, correct?

I saw pictures of your modules with heatsinks. Are those included on the first tier or are those standard of the shelf parts?
Will you include a comprehensive part-list, or maybe offer a full set of parts yourself? Would be nice to have that while the campaign is running to get an idea of the total cost.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 18, 2019, 10:12:20 am
No, a fully assembled unit is not offered through any pledge level. For example, the BB3 2-ch basic contains enclosures and accessories, assembled and tested modules so you only need to have a Philips screwdriver and invest about an hour to connect all to the functional unit (just as was the case with H24005).
The Assembly instructions will be available before the end of the campaign (this (https://www.envox.hr/eez/bench-power-supply/group-buy-kit-assembly.html) is how it looked like for the H24005), and User manual will be also available this time :).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 18, 2019, 10:18:42 am
I saw pictures of your modules with heatsinks. Are those included on the first tier or are those standard of the shelf parts?
Will you include a comprehensive part-list, or maybe offer a full set of parts yourself? Would be nice to have that while the campaign is running to get an idea of the total cost.

This is an fully open source project. Therefore a comprehensive BOMs together with schematics, Gerbers, mechanical parts, etc. are already available on the GitHub. If you're interesting in DCP405 module for instance, you can find everything here (https://github.com/eez-open/modular-psu/tree/master/dcp405) (BTW, used heatsink is an "off-the-shelf" part).

But again, all offered modules will come fully assembled and tested. All what you need to do is to insert it into the BB3 enclosure.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on November 18, 2019, 12:20:45 pm
Well, I want a kit ;)
Some time ago I was on the lookout for a comprehensive kit that builds something useful. Something that is more than a cheap component tester or a LED cube. I missed your previous campaign and am very glad that the EEZ Bench Box gives me a new opportunity.

That BOM example you linked is impressive. So many BOM items, complete with various order numbers  :-+. Seeing that I can understand why you do not want to deal with offering a full kit.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: xlfe on November 18, 2019, 07:54:00 pm
@prasimix I missed out on the eez-h24005 so I was super excited to see the BB3 campaign announcement a few months back. I've been reading through your posts about each module and the more I learn the more impressed I am with the BB3 and the modules.

One thing I was wondering about was whether an option for using your CF-DIC design was part of the campaign instead of the meanwell supplies? It seems like it's not?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 18, 2019, 09:33:45 pm
Unfortunately it is not. The cost was way too high and I also didn't manage to find time and money to proceed with certification.
I've either gave up from QR flyback on the AUX PS module and replace it with Mean Well's 10 W modules because they are certified.
Title: EEZ Bench Box 3 campaign start
Post by: prasimix on November 19, 2019, 02:04:21 pm
It's now official: the campaign start is scheduled for today at 3pm PST (for less then 9 hours). Thanks in advance to all who is going to support this project (as indirectly the EEZ Studio (https://www.eevblog.com/forum/testgear/eez-studio-for-accessing-your-(scpi)-instruments/msg1509535/#msg1509535), too).
Title: Campaign is live!
Post by: prasimix on November 19, 2019, 11:06:48 pm
https://www.crowdsupply.com/envox/eez-bb3/updates/our-campaign-is-live (https://www.crowdsupply.com/envox/eez-bb3/updates/our-campaign-is-live)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: chriswebb on November 19, 2019, 11:28:53 pm
Backed the early bird version!

Looked like they were going pretty quickly. I will need to purchase a third module to complete the enclosure right? Do you have any general recommendations for most useful option? Does the dual output work with the DCP405 modules? Or only with the B variant?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 19, 2019, 11:38:39 pm
Many thanks for support. Any combination of three modules is possible (that's the whole idea of modularity :) and firmware will recognize what is inserted and simply start to use it. Please note that only DCP405 or DCP405B could be coupled in series or parallel on first two slots. I don't know what to suggest as third module, it depends: if you need more channels with lower capability and precision then DCM220 is probably is fine. If you need better overall performance that you should probably go with DCP405B or DCP405.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Helix70 on November 20, 2019, 01:24:38 am
Is there a kit to upgrade an existing H24005 to the EEZ Bench Box 3? Do they use the same AC/DC power supplies and are the modules reuseable? Is it the same case with a new front panel/screen/microcontroller?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Rerouter on November 20, 2019, 01:45:47 am
Got mine ordered. But never saw any update emails
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 20, 2019, 07:17:00 am
Is there a kit to upgrade an existing H24005 to the EEZ Bench Box 3? Do they use the same AC/DC power supplies and are the modules reuseable? Is it the same case with a new front panel/screen/microcontroller?

AC/DC modules are the only part that could be reused from H24005. Everything else (even the DC fan) are different. Therefore a sort of upgrade kit would not save a lot.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on November 20, 2019, 10:16:19 am
Now that the campaign has started, two questions occurred to me:

1. For backers from the EU, can you ship locally? I my opinion it makes little sense to ship your stuff to the USA and then back to me, not to mention the possible tax/import implications.
2. Regarding the Kit: Are there any components that would provide major difficulty regarding had-soldering? BGAs or chips with thermal pads? Am I correct to assume that the MCU is amongst the most challenging components to solder?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 20, 2019, 10:34:59 am
Now that the campaign has started, two questions occurred to me:

1. For backers from the EU, can you ship locally? I my opinion it makes little sense to ship your stuff to the USA and then back to me, not to mention the possible tax/import implications.

The same "issue" we had with last campaign. But last time CS wasn't part of the Mouser and they didn't use their logistics that is doing all clearance at least for EU, etc. Under Fulfillment & Logistics (https://www.crowdsupply.com/guide/fulfillment-and-logistics) you can find this:

VAT and Customs
Crowd Supply pre-pays VAT (GST) and pre-clears customs for all packages shipped to all EU countries, Switzerland, Australia, and Canada. This means the package is delivered directly to the backer's door without the need for the backer to deal with a customs house. For all other countries, the appropriate commercial invoices and customs information is provided with the package, but the backer is responsible for paying any duties and, if necessary, working with their local customs house.
The exact duties levied on a particular package depend on several factors, including the Harmonized Tariff Schedule (HTS) codes of its contents. Crowd Supply will help classify your products with the correct HTS code.


2. Regarding the Kit: Are there any components that would provide major difficulty regarding had-soldering? BGAs or chips with thermal pads? Am I correct to assume that the MCU is amongst the most challenging components to solder?

No QFN or BGA package are present in any modules. However, DCP405/DCP405B has two, and DCM220 has one IC with thermal pad. So far I didn't have any problem to solder them with assistance of the cheapest hot air workstation. Additionally, you can find on the bottom layer that soldering mask is removed beneath that ICs. Therefore you can put additional solder if you are not confident in hot air result.
Since MCU comes in package with exposed pins, total number of pins doesn't make any difference, all what you need is to fix it on 2-3 pins and than proceed with soldering rest. In fact a great fun if you ask me.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: pylo on November 20, 2019, 01:56:02 pm

The same "issue" we had with last campaign. But last time CS wasn't part of the Mouser and they didn't use their logistics that is doing all clearance at least for EU, etc. Under Fulfillment & Logistics (https://www.crowdsupply.com/guide/fulfillment-and-logistics) you can find this:

VAT and Customs
Crowd Supply pre-pays VAT (GST) and pre-clears customs for all packages shipped to all EU countries, Switzerland, Australia, and Canada. This means the package is delivered directly to the backer's door without the need for the backer to deal with a customs house.

If I understand this correctly, that's a real shame. And the way I understand it is that CS will make the VAT+TAX payment easy because they (their logistics partner) will front it, but we backers still have to pay them. And I doubt it'd be any other way: for example, the two-channel basic kit costs 599$ (including the 45$ shipping fee to EU), so the BB3 suddenly costs 713$ (with 19% VAT added) instead of the pledge price of 554$ for somebody in Germany. That's a huge difference. And some countries in the EU have much higher VAT (Hungary for example has 27%). My point is, CS will obviously not take over a fee this high.

What bothers me is not that we have to pay these fees. What bothers me is that we wouldn't have to if you shipped directly within the EU.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 20, 2019, 01:59:32 pm
If I ship it to you directly from Croatia, and you cannot provide valid company VAT number I have to charge you local 25% VAT anyway that is still a little bit lower then Hungarian, but much higher then German.
Title: Current status...
Post by: prasimix on November 21, 2019, 11:12:17 am
We're halfway there! Thanks for spreading a word and support...

(https://pbs.twimg.com/media/EJ5F4jvX0AA4WKa?format=png)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: pylo on November 21, 2019, 02:02:57 pm
Well, that's only the case if we cannot give you a company VAT. I assume many of us here could, though surely not everybody. I think the problem lays probably with how CS intervenes, as we are paying to CS and not to you, so that's probably what makes it unworkable.

By the way, very cool product and I wish you good luck. I already told everybody in the company about it :D  As for me, when I wanted to buy the H24005 about two years ago, it wasn't available anymore, so I had to buy myself a different lab supply from somewhere else. It is only because of this that I am still contemplating if I should back a BB3 or not, because I don't really need a 2nd supply. But the BB3 is very good value and has great features, and if you bring out the other extensions modules in the future, it should be almost unbeatable.

By the way: When do you expect to bring out the other extension modules? I am most interested in the 2Q DC-module if it allows me to avoid buying a separate electronic load. Not to mention all the things I could do with it with some firmware hacking... If that modules happens somewhere in the foreseeable future, that alone could justify buying a BB3 for me, even though I already have a lab supply.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 21, 2019, 02:21:46 pm
Well, that's only the case if we cannot give you a company VAT. I assume many of us here could, though surely not everybody. I think the problem lays probably with how CS intervenes, as we are paying to CS and not to you, so that's probably what makes it unworkable.

That's right.

By the way, very cool product and I wish you good luck. I already told everybody in the company about it :D  As for me, when I wanted to buy the H24005 about two years ago, it wasn't available anymore, so I had to buy myself a different lab supply from somewhere else. It is only because of this that I am still contemplating if I should back a BB3 or not, because I don't really need a 2nd supply. But the BB3 is very good value and has great features, and if you bring out the other extensions modules in the future, it should be almost unbeatable.

Many thanks for good wishes!

The main reason why I gave up from H24005 is limited modularity (and that Chinese guys didn't realize yet that it is worth cloning, so you cannot buy it anywhere :))
The BB3 address that to fair extent with this first chassis that could accept up to three modules that are not necessary DC power sources only.

By the way: When do you expect to bring out the other extension modules? I am most interested in the 2Q DC-module if it allows me to avoid buying a separate electronic load. Not to mention all the things I could do with it with some firmware hacking... If that modules happens somewhere in the foreseeable future, that alone could justify buying a BB3 for me, even though I already have a lab supply.

He, he, I'm thinking about 4Q power module almost from the very beginning of the EEZ adventure. I do believe that its time is coming, first as 2Q (dissipative) module, then as 2Q bidirectional module and finally a 4Q that could used as a SMU. In parallel I'm dreaming about DC power analyzer with 6-channel simultaneous A/D converter (1 x Vin + 2 x Iin, 1 x Vout + 2 x Iout). So, a two current range with continuous sampling on both ranges where firmware will pick relevant range depending of measured current.

The good thing is that we made our "homework" on the firmware and software side so that one could count on rich GUI on TFT touchscreen and PC side for all modules that are coming. If we succeed with campaign will come into position to continue production of all BB3 parts offering in kit but also fully assembled form (we have to pass CE/FCC certification that should start next month) and extend its feature with new modules.
Title: Thanks @bunnie
Post by: prasimix on November 21, 2019, 02:30:39 pm
I couldn't stand not to say what Bunnie (https://en.wikipedia.org/wiki/Andrew_Huang_(hacker)), a great guy who already did a lot for open source/hardware community, said:

https://twitter.com/bunniestudios/status/1197503114246414336
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: jbb on November 21, 2019, 07:52:24 pm
A tweet from Bunnie!  Win!

I've been looking forward to this coming out, so I better get my skates on and order one of these before they sell out...

Do you have any limits on the quantity you'll sell?  (I heard that some campaigns ran into trouble when they planned for 500, got 3500 orders, and found their suppliers and logistics couldn't keep up...)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 21, 2019, 09:53:01 pm
Thanks for the good wishes regarding the final quantity:)
Everything is scheduled for min. 200 units and both of major contractors (enclosure and PCBA) are eager to hear about a 1000 units order (sounds more like wishful thinking for me)! Currently there is a couple of parts with longer lead time (i.e. MCU and power switch) but still the first delivery should remain at a safe 200 units.
I'm not sure that any campaign so far on CS has experienced such an unexpected turn, e.g. that it was planned, as you say, 500 and ended up with 3500. Such success stories happen on Kickstarter and Indiegogo where all media attention is (it seems to me that CS is non existent, people never heard of them, and Alexa ranking, if is accurate, can confirm that). We'll see if I made a mistake this time when I didn't try to organize everything at least on Indiegogo (or indirectly, through an agent even on Kickstarter).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on November 21, 2019, 10:03:01 pm
Well, i ordered a kit.
I now see myself pouring over the BOMs in the next weeks and taking hours to order all the required components  :-/O
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: jbb on November 22, 2019, 12:20:03 am
I hope you get a good number of orders.  Including one from me :-)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: knapik on November 28, 2019, 10:01:53 am
Really cool project and very interested in backing this. I don't have the money to back an entire kit unfortunately, so I may buy the kit and try to build it myself.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 28, 2019, 10:16:36 am
Thanks. When you mention the kit version I assume you mean BB3 Enclosure & Bare Boards. Please note that it does include just few parts (i.e. TFT display, and cooling fan that belongs to wire harness) and all other you have to source by yourself. It should be a big problem since I've prepared detailed BOMs (already available on the GitHub (https://github.com/eez-open/modular-psu)).
Hand soldering should also not be a problem at all: quite the opposite, a very fun process. No QFN or BGA packages, just a few tiny ICs (but with exposed pins) and a couple of them with a thermal pad. I soldered all my prototypes by hand, without stencil, reflow oven, etc.

(http://i.imgur.com/M5yyFHK.png) (https://imgur.com/M5yyFHK)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: knapik on November 28, 2019, 11:16:19 am
Yep the bare boards is what I was referring to in the latter (probably shouldn't have referred to both products as "kits"). Don't worry, I have good soldering skills, its just that building the boards myself allows me to pay for the entire project incrementally.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 28, 2019, 11:18:51 am
Great, don't hesitate to contact me when adventure begins! :-/O
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on November 28, 2019, 04:13:50 pm
By the way, a question in regards to the Kit.
Will we be able to order proper face plates for the modules from you? Getting the holes into a blank plate is one thing, but nice labeling is another ;)

Otherwise, would it be an option to publish gerbers for a pcb as faceplate?

EDIT: And huge  :-+ for the 1click BOMs. Those are great  :)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on November 28, 2019, 04:19:33 pm
By the way, a question in regards to the Kit.
Will we be able to order proper face plates for the modules from you? Getting the holes into a blank plate is one thing, but nice labeling is another ;)

Three predrilled module front panels are included: 2 x DCP405 and 1 x DCM220. Therefore no need for drilling :)

Otherwise, would it be an option to publish gerbers for a pcb as faceplate?

Very good idea, but has to be made on PCB 2 mm thick what shouldn't be an issue.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: alex-sh on November 30, 2019, 11:17:13 pm
I am going to order it now.
Looking very good. When are you expecting to have additional modules please?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 01, 2019, 09:22:49 am
I'm planning to work on few modules during next year: a simple low-speed digital/analog I/O module, 2Q DC power module and DC power analyzer. Of course that is not a job for single person. I believe that I found a good candidate to make 2Q DC power module. Low-speed digital/analog I/O module I should be able to make myself. A great deal of assistance will required for DC power analyzer. In parallel I'll open a project of integration FPGA technology into EEZ BB3 with team behind ULX3S project.
That should be enough tasks to keep me busy for 70-80 hr/week :)
Title: EEZ BB3 data logging
Post by: prasimix on December 01, 2019, 09:43:36 am
An example of why does color touch-screen display on programmable power supply matter. Recording and viewing of the logged data is possible directly on the display. The recorded data is on an SD card and can be transferred with one click to a PC for further processing and analysis thanks to the FOSS multi-platform EEZ Studio application.

https://www.youtube.com/watch?v=ee3jmN_-tKo (https://www.youtube.com/watch?v=ee3jmN_-tKo)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 05, 2019, 08:49:24 am
Hi everyone, the campaign has continued to slow down, but we will try to revive it to some extent with new updates. I would ask for the help of backers and anyone else who finds this project interesting and useful to follow us on Twitter (@envox (https://twitter.com/envox)) and spread the word on social networks and other forums where you are active.

I'd like to encourage potential EU backers once again with the following excerpt (https://www.crowdsupply.com/guide/fulfillment-and-logistics#vat-and-customs) from the Crowd Supply policy:

VAT and Customs
Crowd Supply pre-pays VAT (GST) and pre-clears customs for all packages shipped to all EU countries, Switzerland, Australia, and Canada. This means the package is delivered directly to the backer's door without the need for the backer to deal with a customs house.


Many thanks in advance!
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Towger on December 05, 2019, 08:54:38 am
What country are they being shipped from?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 05, 2019, 08:55:20 am
Portland, OR, USA
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: exe on December 05, 2019, 03:30:57 pm
Would it be possible to buy the device later? I don't need a power supply itself, but I'd like to get an SMU module if/when it's available.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 05, 2019, 03:44:58 pm
Would it be possible to buy the device later? I don't need a power supply itself, but I'd like to get an SMU module if/when it's available.

It's sort of a chicken and egg problem: if we do not succeed with crowdfunding that will lower the chance that we find a way how to finance production of enclosures and basic modules and create a "credit" line with selected manufacturers for production of new units and modules. Therefore, even the small donation could help us to kickstart BB3 production.
Unlike the H24005, which was a one-off production, BB3 was designed modularly to establish continuous production easily and I believe it is feasible.
Title: DCP405 power module advanced features
Post by: prasimix on December 07, 2019, 07:27:33 am
DCP405 power module delivers 0 to 40 V, 0 - 50 mA or 0 - 5 A. This video shows its four advanced features:

https://www.youtube.com/watch?v=5NkEw8b6CAk (https://www.youtube.com/watch?v=5NkEw8b6CAk)
Title: BB3 chassis...
Post by: prasimix on December 12, 2019, 10:17:29 pm
I don't know how to make a poll in existing forum's thread. Therefore I'm copying one that is under way. Your input is highly appreciated:

https://twitter.com/envox/status/1205200299457163264
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on December 12, 2019, 11:01:37 pm
Done; I selected leave as is, although as stated I would prefer USB on front LAN on rear. USB sticks need to be accessible, LAN cables not so much.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 14, 2019, 04:22:47 pm
(http://i.imgur.com/wa4gG9e.png) (https://imgur.com/wa4gG9e)

Thanks all for participation. It seems that mounting connectors on the front panel wasn't as favorable as on the rear panel. According to comments the "truth" is somewhere in the middle: USB on the front, Ethernet on the back.

It could be a first strech goal if we can talk about such thing this time: if we reach 100 KUSD this should be enough to cover the cost of new prototyping and the addition of two cables in all orders.
Title: Power outputs coupling and tracking
Post by: prasimix on December 14, 2019, 10:30:08 pm
A new short video addressing four different types of power outputs coupling performed under firmware control and without need for extra wiring:

https://www.youtube.com/watch?v=I8lTiHVCo1Q (https://www.youtube.com/watch?v=I8lTiHVCo1Q)

Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on December 16, 2019, 04:02:01 pm
Another question regarding the kit recently occurred to me.

What about calibration? What equipment do I need to properly calibrate it?

Regarding the placement of Ethernet and USB: If moving Ethernet to the back would also cause USB to be moved back, then please keep it as it is. USB on the back would be a bigger hassle than Ethernet on the front :) Also I would imagine that would move the SD-Card slot to the back as well. And that just asks for dropped cards  >:D

Using something like a pigtail adapter should reasonably work for both Ethernet and USB though.

Something like these (first hits on google image search)
https://thepihut.com/products/panel-mount-ethernet-rj45-extension-cable (https://thepihut.com/products/panel-mount-ethernet-rj45-extension-cable) (with a longer cable of course)
And this:
https://www.ebay.com/itm/10pcs-RJ45-Network-Ethernet-8P8C-Socket-Connector-8Pin-Vertical-180-PCB-Mount-/192847609885 (https://www.ebay.com/itm/10pcs-RJ45-Network-Ethernet-8P8C-Socket-Connector-8Pin-Vertical-180-PCB-Mount-/192847609885)

Your are only running 100Mbps, so using such an adapter cable will not be an issue.
Bonus points for keeping the ethernet status LEDs on the front  ;D
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 16, 2019, 04:15:10 pm
Another question regarding the kit recently occurred to me.

What about calibration? What equipment do I need to properly calibrate it?

If you are backed kit with assembled modules than you don't need to do anything. All modules will come calibrated to the extend of what my FLUKE287 could provide. Anyway the calibration is a simple process: you have to follow calibration wizard steps as described in User manual (https://github.com/eez-open/modular-psu/blob/master/docs/user%20manual/EEZ%20BB3%20user%20manual%20DRAFT%200.2.pdf) (Chapter 13).

Regarding the placement of Ethernet and USB: If moving Ethernet to the back would also cause USB to be moved back, then please keep it as it is. USB on the back would be a bigger hassle than Ethernet on the front :) Also I would imagine that would move the SD-Card slot to the back as well. And that just asks for dropped cards  >:D

Using something like a pigtail adapter should reasonably work for both Ethernet and USB though.

Something like these (first hits on google image search)
https://thepihut.com/products/panel-mount-ethernet-rj45-extension-cable (https://thepihut.com/products/panel-mount-ethernet-rj45-extension-cable) (with a longer cable of course)
And this:
https://www.ebay.com/itm/10pcs-RJ45-Network-Ethernet-8P8C-Socket-Connector-8Pin-Vertical-180-PCB-Mount-/192847609885 (https://www.ebay.com/itm/10pcs-RJ45-Network-Ethernet-8P8C-Socket-Connector-8Pin-Vertical-180-PCB-Mount-/192847609885)

Your are only running 100Mbps, so using such an adapter cable will not be an issue.
Bonus points for keeping the ethernet status LEDs on the front  ;D

For now, both connectors remain on the front panel as the additional cost of prototyping and cabling goes out of the campaign budget. This will be set up as the first stretch goal, but I have already made a new variant of the MCU PCB where the connectors have been removed to the rear. Currently both versions are on GitHub (https://github.com/eez-open/modular-psu/tree/master/mcu): r1B6 and r2B1. Here's what r2B1 looks like:

(http://i.imgur.com/6jOydfN.png) (https://imgur.com/6jOydfN)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: dunkemhigh on December 16, 2019, 05:17:19 pm
I am not a part of this (yet!) but perhaps I could make a suggestion...

What I see here is the PSU taking up significant space on the bench, which should be given over to whatever is being worked on rather than the tools. The PSU could be moved to, say, a shelf but then it would be a real drag to drive that touchscreen with one's arm at full stretch and an upward 45 degree angle.

How about a remote front panel? I don't mean remote control feature for, say, a PC or phone. I mean that actual front panel we see there but on its own with none of the rest of the stuff. It would take up no room at all, be highly maneuverable (on the end of a bit of cable, but could be wireless?) yet still give the full features and feel of the real thing. After all, that's the bit you want to mess about with - once your power cables are connected you're not going to be swapping them around every 5 seconds so the hardware side of the PSU can be well out of reach.
 
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 16, 2019, 05:40:26 pm
Huh, that sounds like a real challenge! That could be possible but I'm concerned about the cost of such solution. A remote "terminal" should be housed in something nice but robust, perhaps a custom made plastic enclosure. Maybe not, if something suitable already exists. Otherwise only making a custom casting tool will cost a fortune.
But there is two other possibility: one is completely crazy and that is to rotate enclosure in "portrait" position such as mini tower PC enclosures and rotate all screen contents. Another one you are already discarded, but I'll mention it: use some of MQTT clients for "smart" phone and arrange your own dashboard. That shouldn't be a big task (no real programming is involved).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: dunkemhigh on December 16, 2019, 06:00:48 pm
I guess a tablet would work if it replicated the front panel closely.

Just an idea :)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on December 16, 2019, 06:30:58 pm
I remember in one of the BB3 threads the suggestion about adding a small hardware keyboard to control the BB3. I thought that idea was really neat and hope something like that gets implemented at some point.

I honestly do not know if it makes really sense to talk about stretchgoals though at this point. If the funding keeps going at this rate the BB3 will barely make it...
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on December 16, 2019, 08:20:14 pm
I'm concerned like Ranaya, the BB3 appears to be stalling. I suspect that people are looking at it as a replacement for their current power supply or even a more competent version of something they already have. It is SO MUCH MORE. It's a test system.

With the ability to slide in and out various programmable modules, much of the hack work that goes into testing can be done by the machine with the results recorded for later analysis.

Prasimix in his first video mentioned what they have in the works - but I know others have suggested a data logger, 2Q, audio test and other options.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 17, 2019, 09:34:15 am
I remember in one of the BB3 threads the suggestion about adding a small hardware keyboard to control the BB3. I thought that idea was really neat and hope something like that gets implemented at some point.

I'm more interesting in adding support for my old USB Sony foot pedal FS-85 (https://www.sony.com/electronics/support/audio-video-accessories-portable-audio-accessories/fs-85usb) (there is few others used in dictation solutions). It has three switches like left-up-right that can be used for e.g. increase-decrease selected voltage or current, turns OE on or off, etc. and leave both hands free for other activities.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on December 17, 2019, 07:53:52 pm
But tapping your feet to the music may be a problem.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on December 18, 2019, 08:05:59 am
I have not looked at the SCPI protocol at all.
But from what I can glean from the descriptions, it looks as if that would allow remote control of many functions of the BB3.

Since the BB3 has SCPI over Ethernet, even standalone wireless control panels should be possible.

In that regard, as I said not knowing anything about SCPI, or how the BB3 implements it, is there any security in place for remote SCPI access?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 18, 2019, 08:14:51 am
SCPI is "plain stupid" text protocol for communication with various T&M devices. Therefore security has to be managed on some other (lower) layer. It's suitable for closed, non-encrypted lab's LANs. For accessing device outside LXI (https://en.wikipedia.org/wiki/LAN_eXtensions_for_Instrumentation) should be implemented that require HTTP server or HTTPS server for security reasons. Other possibility is to use MQTT on which we are currently working and first demo will follows soon. Perhaps we should "encapsulate" SCPI commands in MQTT messaging.
Title: BB3 web simulator
Post by: prasimix on December 18, 2019, 08:28:25 am
Feel free to explore most of the implemented SCPI commands using Web simulator (https://www.envox.hr/eez-modular-firmware-simulator/). SCPI commands are listed in Chapter 4 (https://www.envox.hr/eez/eez-bench-box-3/bb3-scpi-reference-manual/bb3-scpi-common-command-reference.html) and Chapter 5 (https://www.envox.hr/eez/eez-bench-box-3/bb3-scpi-reference-manual/5-subsystem-command-reference.html).

(http://i.imgur.com/Z9bmTbg.png) (https://imgur.com/Z9bmTbg)
Title: First MicroPython script - simple diode tester
Post by: prasimix on December 19, 2019, 06:32:40 pm
Here we go, the MicroPython in action. First script is simple diode tester, more to come. Link to script: https://github.com/eez-open/modular-psu/blob/master/MicroPython/diode-tester.py (https://github.com/eez-open/modular-psu/blob/master/MicroPython/diode-tester.py)

https://www.youtube.com/watch?v=r0kx4t4qeRc (https://www.youtube.com/watch?v=r0kx4t4qeRc)



Title: Re: First MicroPython script - simple diode tester
Post by: AlanS on December 19, 2019, 10:20:12 pm
Here we go, the MicroPython in action. First script is simple diode tester, more to come. Link to script: https://github.com/eez-open/modular-psu/blob/master/MicroPython/diode-tester.py (https://github.com/eez-open/modular-psu/blob/master/MicroPython/diode-tester.py)

https://www.youtube.com/watch?v=r0kx4t4qeRc (https://www.youtube.com/watch?v=r0kx4t4qeRc)

Wonderful stuff.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on December 21, 2019, 10:14:00 am
I have now additionally backed a full unit. There goes my christmas bonus ;)

After seeing all the updates I want to make sure I have a unit that works  ;D
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 21, 2019, 10:34:42 am
I have now additionally backed a full unit. There goes my christmas bonus ;)

After seeing all the updates I want to make sure I have a unit that works  ;D

Thanks! Looking forward to see more backers follow your and danielbriggs example (https://www.eevblog.com/forum/projects/eez-h25005-a-possible-successor-of-eez-h24005-programmable-power-supply/msg2835508/#msg2835508) :-+. Especially backers from EU, AUS, CAN, CH.
Title: EEZ BB3 MQTT support
Post by: prasimix on December 25, 2019, 08:18:58 am
Another video, this time how to make BB3 a useful I(di)oT :)

https://www.youtube.com/watch?v=THyfLSSAhrI (https://www.youtube.com/watch?v=THyfLSSAhrI)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 28, 2019, 09:12:03 am
Thanks Dave!

https://twitter.com/eevblog/status/1210721505195118593 (https://twitter.com/eevblog/status/1210721505195118593)

(http://i.imgur.com/ldclUA3.png) (https://imgur.com/ldclUA3)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on December 28, 2019, 04:01:55 pm
 :-+ If that does not push the BB3 over the funding edge...

It already has started to go faster right after christmas. I guess more people spending their christmas money ;)

Well time to look into ordering components.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on December 28, 2019, 10:13:44 pm
:-+ If that does not push the BB3 over the funding edge...

It already has started to go faster right after christmas. I guess more people spending their christmas money ;)

Well time to look into ordering components.

I'm hoping Dave has pushed this over the edge. But it is SO MUCH MORE than a power supply.

It's the BB3's versatility that makes it 2019's standout open-source bench instrument.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: mcdanlj on December 30, 2019, 11:05:01 pm
[attachimg=1]

 :-+
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on December 30, 2019, 11:21:03 pm
Whhoo-Hoo!! You must have been refreshing the page as often as I was.

All of a sudden that stretch goal looks achievable.  :box:
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: dunkemhigh on December 30, 2019, 11:24:56 pm
Well done!

I'd love one of these but can't justify the cost, sadly.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on December 31, 2019, 08:17:45 am
(http://i.imgur.com/EhYzoJY.png) (https://imgur.com/EhYzoJY)
Title: EEZ BB3 protection mechanisms
Post by: prasimix on January 01, 2020, 07:03:59 am
A short video about various built-in protections like the detection of cooling fan failures, output states on power up and protection trip, full-range OVP crowbar, display lock, module power failure, reverse polarity protection of both power outputs and remote sense inputs, power recycling with connected battery, and inhibit mode.

https://www.youtube.com/watch?v=ldEfRlDZdyk (https://www.youtube.com/watch?v=ldEfRlDZdyk)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on January 02, 2020, 02:10:07 pm
Congratulations  :-+
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: knapik on January 03, 2020, 09:05:24 am
Just made an order for the bare boards + enclosure (sorry it took so long to do).
Congratulations on meeting the funding target!
Title: Simple curve tracer
Post by: prasimix on January 04, 2020, 07:33:06 am
MicroPython scripting is used to create curve tracer for NPN BJTs and N-ch MOSFETs.

https://www.youtube.com/watch?v=I0y6fgv8G00 (https://www.youtube.com/watch?v=I0y6fgv8G00)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 05, 2020, 07:42:14 am
Shortly we'll enter the final countdown (last 48 hours). We are missing little below $6K to reach stretch goal ($100K). After that campaign will enter pre-order period when the following changes will happen:
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 05, 2020, 07:56:50 am
Current ranking list of our backers still include US, Australia and Germany on the first three positions. Actually, most of backers comes from California, strange isn't it :).
We are really missing this time folks from Austria, Italy, Spain and Russia.

(http://i.imgur.com/SPvkYJy.png) (https://imgur.com/SPvkYJy)

(http://i.imgur.com/1bfRbGL.png) (https://imgur.com/1bfRbGL)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: jan28 on January 05, 2020, 08:40:44 pm
Thank you for the inspiring design and congratulations on meeting the funding goal.

What will happen to the price of the "BB3 - Starter (Without Peripheral Modules)"?

I'm still in doubt wether to order this in addition to the full unit now. I want to have space for future modules because I see a lot of potential for interesting modules (loads, low power measurement, references, waveforms, USB PD, ...).
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 05, 2020, 10:41:44 pm
Thanks for your support. This pledge level is not yet discussed with CrowdSupply team. In a worst case scenario it price could rise for a few percentage.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: mcdanlj on January 06, 2020, 12:23:43 am
Shortly we'll enter the final countdown (last 48 hours).

Thanks for the details on the changes. What's the precise cut-off time in UTC for the campaign?

Any more thoughts on making it possible to keep front-panel USB at least as an option if you make the $100K stretch goal?
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on January 06, 2020, 01:11:35 am
Shortly we'll enter the final countdown (last 48 hours).

Thanks for the details on the changes. What's the precise cut-off time in UTC for the campaign?

Any more thoughts on making it possible to keep front-panel USB at least as an option if you make the $100K stretch goal?

It looks like you can see the time left to run on the top RHS of this screen. About 46 hours to go as of this post. https://www.crowdsupply.com/envox/eez-bb3/updates/our-campaign-is-live (https://www.crowdsupply.com/envox/eez-bb3/updates/our-campaign-is-live) 
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 06, 2020, 07:46:57 am
Any more thoughts on making it possible to keep front-panel USB at least as an option if you make the $100K stretch goal?

It will be difficult to keep both versions if we are going to move connectors to the back. I have few enclosures with connectors on the front left from test run is someone is interesting, but MCU module one has to build its own, i.e. order r1B6 PCB and parts, or move parts from assembled new design (r2B2) and solder them to the r1B6 PCB.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: mcdanlj on January 06, 2020, 12:25:04 pm
It looks like you can see the time left to run on the top RHS of this screen. About 46 hours to go as of this post.

Yeah, when I asked it was showing only days. Changed shortly after I asked. ☺

Any more thoughts on making it possible to keep front-panel USB at least as an option if you make the $100K stretch goal?

It will be difficult to keep both versions if we are going to move connectors to the back. I have few enclosures with connectors on the front left from test run is someone is interesting, but MCU module one has to build its own, i.e. order r1B6 PCB and parts, or move parts from assembled new design (r2B2) and solder them to the r1B6 PCB.

Oh, I was hoping for using cables to remote the port from the board to a case cutout, as typical for PC motherboards and USB ports in a case. But I'll "stay on the reservation" and get whatever everyone else gets.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 06, 2020, 12:30:03 pm
My idea is to use this type of cables:

(http://i.imgur.com/h9DULeY.png) (https://imgur.com/h9DULeY)

(http://i.imgur.com/casBe3p.png) (https://imgur.com/casBe3p)

I think that we'll need another round of voting like:

1. Move both sockets to the rear
2. Move only Ethernet socket to the rear

New MCU is presented here (https://www.eevblog.com/forum/crowd-funded-projects/eez-bench-box-3-sequel-to-eez-h24005/msg2831680/#msg2831680) (if we are going with solution #1), but another revision will include jbb's suggestion to move BOOT0 switch from AUX PS to MCU.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on January 06, 2020, 07:44:53 pm
28hrs left, $99,719 raised....
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: peteb2 on January 06, 2020, 10:21:06 pm
I supported the H24005, which has been a hoot to use experimenting, testing & doing repairs. Wasn't hard to support this latest project therefore and quite possibly the last time i will ever need to buy a bench powersupply (that can do so much more)!
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 06, 2020, 10:36:28 pm
Thanks everyone for support! A new voting is opened on twitter: https://twitter.com/envox/status/1214314436359532544
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 08, 2020, 11:43:11 am
The crowdfunding part of the campaign is now finished. We have backers from 32 countries. Thanks to all!

Now I have to decide what to do with Ethernet and USB sockets. Twitter voting is closed with two votes more for moving both sockets to the rear. If we add votes from another thread (https://www.eevblog.com/forum/projects/eez-h25005-a-possible-successor-of-eez-h24005-programmable-power-supply/msg2860224/#msg2860224) then 4 more votes goes against moving USB to the rear.
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: Ranayna on January 08, 2020, 11:59:58 am
Since you seem to plan using those pigtails you linked, the difference regarding the locations of the ports seems to be just the place where to mount the cable, right?
Ok, keeping the existing locations as-is would likely not be possible since the PCB will be in the way, but would it not be possible to have some holes, covered with removable blanking plates, on the front and back so that it would be easily possible to move the cable? I do not know though how to do that without ruining the looks of the box and how much cost this would add.

Anyway, if this has to be a decision that has to be made now, I will agree with danielbriggs:

I don't have Twitter so can't vote.

My vote is:
If it's USB Host / mass storage [USB on front, Ethernet on rear]
If it's USB Device to plug into a PC [Both USB and Ethernet on rear]
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 08, 2020, 12:30:03 pm
Thanks for your input. I'm also more in favor of leaving USB on the front panel, since It is planned to be host also. Perhaps we can add "blind" hole on the rear for people who is willing to move USB to the rear, but for that I have to include place for pin header (since there is available ready made USB patch cable with 0.1" receptacle on one end). More importantly I have to check if RJ45 socket is allowed to be placed on the opposite edge of the PCB since it may now interfere with AC/DC modules that are hanging down from the top cover!
Title: BB3 fulfillment, week #1 update
Post by: prasimix on January 14, 2020, 03:55:33 pm
Since I don't have my own blog, I decided to post campaign fulfillment weekly updates here (important info will be post on the Crowd Supply, too). I'll try to do that every Tuesday until everything is finished. In week #1 we did the following:

1. Sent latest BOM's to PCBA manufacturer to get delivery estimation
2. Made change on MCU module, where only Ethernet is moved to the rear
3. Contacted enclosure manufacturer regarding new prototype. They'll try to make a new front and rear panels and AC/DC converters mounting frame and send them to me ASAP
4. Still discussing with Crowd Supply campaign balance sheet that will be used as basis for funds transfer
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: AlanS on January 14, 2020, 08:39:20 pm
I'd be curious to know your feelings on dealing with Crowd Supply - but wait until you get your money! :-+
Title: Hook-on probes
Post by: prasimix on January 16, 2020, 05:16:37 pm
I need your feedback here. Pledge level "cable set" include red-black pair of hook-on probe. The price is the same, but dimensions and design differs. Link to online poll (with pictures):

https://www.surveylegend.com/s/1z4k (https://www.surveylegend.com/s/1z4k)
Title: Re: Hook-on probes
Post by: Andrew McNamara on January 16, 2020, 11:17:10 pm
I need your feedback here. Pledge level "cable set" include red-black pair of hook-on probe. The price is the same, but dimensions and design differs. Link to online poll (with pictures):

I found I couldn't choose - on the one hand, right-angle is cute, but clip is also quite a bit bigger, which might negate the right angle somewhat. I think I will be happy with either.
Title: Re: Hook-on probes
Post by: prasimix on January 19, 2020, 08:10:21 am
I need your feedback here. Pledge level "cable set" include red-black pair of hook-on probe. The price is the same, but dimensions and design differs. Link to online poll (with pictures):

https://www.surveylegend.com/s/1z4k (https://www.surveylegend.com/s/1z4k)

Survey is closed, thanks for your participation. You confirmed what I initially wanted to deliver: ELECTRO-PJP 404-890 (overall size: 76 mm)
Title: BB3 fulfillment, week #2 update
Post by: prasimix on January 21, 2020, 05:38:22 pm
Progress from last week:
Step response for 5 A range before:

(http://i.imgur.com/a6Dh7Fn.png) (https://imgur.com/a6Dh7Fn)

Step response (Vset=5 V, Iset=0-49 mA step, load=16R4) for 5 A range after correction:

(http://i.imgur.com/p1Zwttk.png) (https://imgur.com/p1Zwttk)

It is now pretty much in line with 50 mA range response:

(http://i.imgur.com/xBWedbE.png) (https://imgur.com/xBWedbE)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: jbb on January 24, 2020, 06:47:45 am
Ah, Chinese New Year. For once it’s not biting me in the backside. Yet.

I previously asked about changes to the MCU board. Given the Ethernet is moving, did you find room to move the BOOT switch from the aux board to the main board?

(I was a little worried about how close the tracks got to the 240 V AC lines and spied an opportunity to move it all away.)
Title: Re: EEZ Bench Box 3 - Sequel to EEZ H24005
Post by: prasimix on January 24, 2020, 07:11:03 am
Given the Ethernet is moving, did you find room to move the BOOT switch from the aux board to the main board?

Yes, both BOOT switch and battery holder to accept CR2032 instead of CR2025. PCB layout pictures: https://github.com/eez-open/modular-psu/tree/master/mcu/Images