Siglent SPD3303X-E Hi-Resolution Output Unlock?

[MotoDan]

Hello all,

Just picked up a Siglent SPD3330X-E supply and thought it might be nice to increase it's voltage and current resolution from 10mV/10mA to the 1mV/1mA that is offered on the SPD3303X supply. Has anyone come up with a hack for this change?

BR's

[tautech]

Yep, very possible.

See here:
https://www.eevblog.com/forum/testgear/siglent-ads-firmware-file-format/msg1830584/#msg1830584

[DaJMasta]

It's in the SPD3303X-E thread (or was it the Siglent .ads thread...), you download a modified firmware update, connect it to your computer, and use the software to update the firmware, which enables the high resolution mode.  Very quick to do, over USB.  should be just a search away.

[MotoDan]

Awesome, Thanks tautech & DaJMasta! I look forward to the upgrade.

BR's

[gorillamotors]

Just got my 3303X-E in yesterday and modified it. Works good. My question is if there is a new firmware update will it overwrite the hack back to the X-E?

[BillB]

Just got my 3303X-E in yesterday and modified it. Works good. My question is if there is a new firmware update will it overwrite the hack back to the X-E?

Good question, I think it might as it is a product-id replacement.  However, these power supplies aren't like the scopes in that there have been very few firmware updates because there just aren't that many features.  Perhaps if they add/flesh-out SCPI commands or something then there might be another firmware update, but I'd actually be surprised to see another update for the current models.

[tv84]

Just got my 3303X-E in yesterday and modified it. Works good. My question is if there is a new firmware update will it overwrite the hack back to the X-E?

That won't happen because, in FW terms, your equipment is a X version now. So, you'll only be able to install the X version FW, from now on.

[sjm]

Yep, very possible.

See here:
https://www.eevblog.com/forum/testgear/siglent-ads-firmware-file-format/msg1830584/#msg1830584

Thanks! Today I finally got into this and it worked. Had to retry flashing several times, but it was a success after all.

BR, -sjm

[tkhater]

Just wanted to add, I just got this to work as of today, with new equipment purchased from Amazon.

Mine came from the factory with the 1.01.01.02.07R2 firmware.

I did the upgrade as described above.  I did it via USBTMC.  Just as a note, when I sent the "FACTORY ON" command, I got no response from the unit so I was not sure anything happened.  There were a lot of times during this process when I had to restart the EasyPower software and unplug/replug the USB in order to get EasyPower to see the Siglent.  Nonetheless, when it saw the unit, the upgrade proceeded without a hitch.

I flashed the modded firmware, which was 2.05.

I rebooted, and it came up with high resolution mode.

I reflashed the original firmware downloaded from siglentna.com

It came back up with the latest version in high resolution mode.  It reported back as an SPD3303X, and NOT a SPD3303X-E.

Cheers.

[blurpy]

Just wondering what the accuracy is like after an upgrade like that? I guess it's calibrated as a 10mV/10mA device even though it can do 1mV/1mA. In that case it's probably random how accurate it is on the 1mV/1mA range?

[tv84]

Just wondering what the accuracy is like after an upgrade like that? I guess it's calibrated as a 10mV/10mA device even though it can do 1mV/1mA. In that case it's probably random how accurate it is on the 1mV/1mA range?

What is the probability of something that is random in between 1-9 tenths and then, when you reach the full tenth (10, 20, 30 etc.), it gets accurate?   

[tautech]

Just wondering what the accuracy is like after an upgrade like that? I guess it's calibrated as a 10mV/10mA device even though it can do 1mV/1mA. In that case it's probably random how accurate it is on the 1mV/1mA range?

Precision can be trimmed.
See Chapter 3 Calibration instructions in the Service manual:
https://www.siglenteu.com/wp-content/uploads/dlm_uploads/2019/07/SPD3000X-Series-Service-Manual.pdf

[blurpy]

What is the probability of something that is random in between 1-9 tenths and then, when you reach the full tenth (10, 20, 30 etc.), it gets accurate?   

What is the probability of it being accurate on the full tenth if you only test in increments of 10?
Lets say Siglent tests it with a load of 10mA and it displays 0.01A, and with a 20mA load it displays 0.02A. That looks perfect. Then a user upgrades and gets an extra digit. With a 10mA load, what does it display? Perhaps 0.010A? Perhaps 0.019A? It could be perfectly spot on, or up to 9mA off.

But I have no clue how they do this, so they might also do calibration in a way that the tens are verified to be accurate.

Precision can be trimmed.
See Chapter 3 Calibration instructions in the Service manual:
https://www.siglenteu.com/wp-content/uploads/dlm_uploads/2019/07/SPD3000X-Series-Service-Manual.pdf

Thanks!

[2N3055]

I would presume calibration is automated, so all readouts and writes to PSU are over SCPI. Which might have full resolution. There are many instruments that return additional digits (more than on screen) over SCPI.. So it might be as well that it is calibrated in full precision despite display not showing last few digits..

[mawyatt]

Just wondering what the accuracy is like after an upgrade like that? I guess it's calibrated as a 10mV/10mA device even though it can do 1mV/1mA. In that case it's probably random how accurate it is on the 1mV/1mA range?

Precision can be trimmed.
See Chapter 3 Calibration instructions in the Service manual:
https://www.siglenteu.com/wp-content/uploads/dlm_uploads/2019/07/SPD3000X-Series-Service-Manual.pdf

Recall following this cal procedure when we got our first SPD3303, results were OK. Now need to do same on the one we just received, but it's already involved in a setup {need +- 12V, +5V (variable), +1V (variable), +2.5V (variable), +5V, +6V and +-100V } along with the first, so this cal procedure will have to wait.

Best,

[mawyatt]

We got a few moments of "free time" and followed up with the second 3303X-E calibration. As mentioned this second 3303X-E was required to support and on-going design effort, it was "enhanced" to a 3303X following the procedures outlined here, same as was our first 3303X-E awhile back.

The 1st 3303X is used to supply critical voltages to expensive chips and has the current limits set to under 20ma, just above the normal operating currents. This has already saved the day A certain dumb arse we won't mention used a standard Raspberry Pi breakout PCB for the 40 pin GPIO connector to get access to the 40 analog DAC channels which are on a 40 pin header and are used to drive HV amplifiers, Bi-Phase modulators and Bi-Polar offset modes in another custom PCB. When the system was turned on and commands sent via SPI to activate the various individual channels, certain channels would cause an overcurrent condition and the 3303X would go into a limit condition. This was thought to be due to shorts on the 100 pin LQFP device, after carefully viewing and probing under a microscope this was not the case, which then led to examining all the custom PCB traces for possible shorts without any discovered. So back to the setup but without the IO connector in place, no overcurrent, but with the IO connector and overcurrent condition Turns out the breakout PCB doesn't route each individual pins to the male connector as expected, but ties the various common pins of the Raspberry Pi GPIO together, thus shorting certain pins as experienced

Anyway, the second 3303X was used for a more general supply of for VCC and VEE use and current limits set to an arbitrary 100ma and not verified. After calibration it was noted the  current limit was engaged at ~80ma on both channels without any load!! This was thought to be a calibration issue and all the memory was reset and another calibration performed, the result was the same. After many memory and power resets, multiple calibration attempts, this condition still resides even tho the current readings are very accurate over the entire range, as are the voltage readings. This high OC condition seems to be an offset since the readings at actual currents also show an offset of similar value (~80ma). Both supplies exhibit very accurate voltage and current readings over the supplies full range, however only one has the correct current limit settings which are quite accurate, even at the lower ranges which was impressive performance IMO.

Both have the same firmware (1.01.01.02.05), same hardware (V3.0), same product type SPD3303X, so beginning to think this second unit has a hardware issue with the current limit circuit.

BTW I had no idea just how good this supply is regarding voltage, current and current limit accuracy (one at least), until we needed a precision voltage with low current limit and it save our butt

Would appreciate if a few others with these "enhanced" 3303X-E could check the current limits at lower levels like 40ma, 20ma and 10ma and report results.

Thanks in advance for any help.

Sorry for the long thread, but figured others might appreciate how this all transpired, and why a precision supply is very valuable for lab use.

Best,

Edit: Here's the setup for the project with only 4 channels, will grow to at least 64 and likely 100. Of course the multiple instances of these PCBs will be integrated into a custom PCB base, and all the Power Supplies (+-75V, +-7V, +5V, +5.5V, +6V) will be replaced with a custom PS running from a single 12V input also supporting custom computer interfaces with USB, SPI and RPi interfaces.


 

[mawyatt]

Update, just contacted Saelig in NY where we purchased the SDP3303X-E. They have issued a RMA and sent another SPD3303X-E as a replacement 

Talk about value added distribution service, here is an example 

Best

[mawyatt]

Follow up on this. The replacement was just received and checked out, decided to "enhance" which was successful, so now a 3303X. Then a cal procedure as outlined in the service manual using a KS34465A and SDL1020X-E. The voltage and current calibrated well, but now the current limit is hosed up like the other. I know suspect something in the cal procedure we did is wrong, but been thru this multiple times and from different perspectives, same result.

Here's what's happening. After the setup and access thru VISA per manual instructions, a *IDN? is sent and everything checks out. Then a *CALCLS 8 is sent to clear all the ch1 and ch2 coefficients, then ch1 voltage calibration is followed and saved with *CALST command, then ch2 voltage, then ch1 current and finally ch2 current. The voltage outputs on Ch1 and Ch2 are spot on, as are the current readings, however the no load current limit is now ~100ma on both channels!!

Repeat the *CALCLS 8 to reset all the coefficients and noted that the no load current reading on ch1 is ~100ma and ch2 ~85ma and this is where the no load current limit trips on both channels. After a current calibration the current readings are correct but the current limit is not, it still has this ~100ma offset and still trips at ~100ma no load. So the current limit trips at the setting plus ~100ma, so for example if I set the current limit to 300ma, then the actual current of ~200ma will cause a current limit.

Then tried a *CALCLS 2 and *CALCLS 3 which clears the current settings and readings with same result as above. So it seems this is an issue in the calibration procedure with an enhanced 3303X-E.

Anyone experience this type of current limit issue?

I guess the next step is to revert back to the 3303X-E and hope this current limit issue doesn't follow.

Edit: Tried to revert back to the 3303X-E from the 3303E we now have to see if this current limit issue can be corrected. With help from tautech we were able to do this with the 3303X that has the .05 firmware version, the other 3303E has the later .07R2 firmware and the proper files back on the Siglent thread (https://www.eevblog.com/forum/testgear/siglent-ads-firmware-file-format/msg1830584/#msg1830584) only support the older .05 firmware (later files may be available tho). Eventually we were able to get back to a base line 3303X-E, however the dreaded current limit offset followed. Tried a couple CAL procedures without success, and not sure what to try next.

A possible warning to others that make the 3303X-E to X enhancement, be very careful if you decide to do a calibration. I've hosed up the current limit on two units now, and can't figure out how to correct this. Believe me we've tried at least 50 calibration attempts, cycled power 20 times, tried various ways including some on USB, others on LAN, and wasted 2 days at this. Nothing seems to dislodge this current limit offset, it even transitions firmware changes, the voltage and current readings are good tho so the supplies are not totally bricked.

One telltale symptom was when *CALCLS 8 was invoked, the no load current reading jumped up ~100ma from 0 and this became the current limit offset which doesn't get corrected when the current calibration is performed. The current limit must be set much higher than 0 even without a load and the real current limit is the setting minus this offset, so if you want 50ma, then you must set the current limit to 50ma + the offset.

Any help or insight with this issue is greatly appreciated.

Best,

[blurpy]

Wow, scary. Perhaps tautech can test calibration on a stock X-E (or X) to see if it's related to the modification, or just a buggy calibration feature in general?

[tautech]

Wow, scary. Perhaps tautech can test calibration on a stock X-E (or X) to see if it's related to the modification, or just a buggy calibration feature in general?

We have already shared many emails. 

All stock sold so none available to do checks on.   
However after receiving a nice SPD series adjustment PDF from the factory not long ago it's already in mawyatt's inbox for when he awakes.

[mawyatt]

Unfortunately the factory PDF is just a text version of the Calibration procedure is the Service Manual, so this does not correct the no load current limit offset issue.

We haven't found any technique to reset the no load offset current back to 0, nothing has worked. We have another SPD3303X-E arriving this week, and will not be attempting any calibrations on this unit if we decide to enhance it to a 3303X.

So think Caution is still applicable until a means to reset the no load current limit is found.

Best,

[boggis the cat]

You mention a 100 mA offset.  I noticed this part of the cal adjustment procedure:

"(1) Connect the output of the channel to be calibrated to the output of the electronic load, and set the electronic load to constant current mode, set the constant current value to 100mA."
(On page 32 of "SPD3000X-Series-Service-Manual.pdf".)

Are you sure that you're following the procedure correctly?

We have two of these instruments at work, but have not had a reason to attempt adjustment.

[TheDefpom]

My experience doing this kind of cal stuff with gear is that sometimes they don’t actually use a “0” cal point, but something other than 0, it sounds like you should be loading the unit up with 100mA and then doing that part of the cal so it sets its 100mA point when it is actually supplying 100mA, and then moving on from there.

I haven’t read the cal procedure for these units, but from what you have written I am 99% sure that is what is wrong.

[TheDefpom]

Ok, I am reading the service manual right now…

Shown for Ch1, change channel to Ch.2 once ch1 done.

This sets the 100mA cal point: CALibration:CURRent ch1,3,NR3 (with NR3 being the actual current present with the load set to 100mA)

This sets the 2.5A cal point: CALibration:CURRent ch1,4,NR3 (with NR3 being the actual current present with the load set to 2.5A)

It is a bit confusing in the manual where it also has a DISPLAYING calibration section too, which is basically identical apart from the ch1,3 being ch1,1 and ch1,4, being ch1,2 instead.

[mawyatt]

You mention a 100 mA offset.  I noticed this part of the cal adjustment procedure:

"(1) Connect the output of the channel to be calibrated to the output of the electronic load, and set the electronic load to constant current mode, set the constant current value to 100mA."
(On page 32 of "SPD3000X-Series-Service-Manual.pdf".)

Are you sure that you're following the procedure correctly?

We have two of these instruments at work, but have not had a reason to attempt adjustment.

Yes, followed it exactly as outlined in the manual multiple times, then tried multiple variations, always with the same result the current limit or CC without any load goes into CC mode (current limit) and the CC LED turns Red indicating an current limit or overcurrent condition. We could not get the CC mode to disengage with no load until the CC setting was increased to ~100ma, which means that without any load current the CC setting must be greater than this current offset (which should be ~0 normally). If you set your load current to 50ma then you must set the 3303X to this offset current plus the load current, or 100ma offset + 50ma load or 150ma. So the cal procedure has introduced a CC offset that can't be removed by any means we've tried.


Best,