Author Topic: Components you wish existed.  (Read 37122 times)

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Offline Neomys Sapiens

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Re: Components you wish existed.
« Reply #200 on: October 12, 2017, 10:30:59 pm »
A little box, containing the necessary components for making modular rotary switches for ALL the options that are possible (normal break-before-make, make-before-break, and shorting (all up to the current position).
For PCB and free mounted ones, in a high quality and reliability version. Also momentary with return, two steps on each side, and coaxial ones.
 

Offline coppice

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Re: Components you wish existed.
« Reply #201 on: October 13, 2017, 09:32:12 am »
A little box, containing the necessary components for making modular rotary switches for ALL the options that are possible (normal break-before-make, make-before-break, and shorting (all up to the current position).
For PCB and free mounted ones, in a high quality and reliability version. Also momentary with return, two steps on each side, and coaxial ones.
Kits like that were common in the 60s and 70s. I haven't seen one for decades, though.
 

Offline precaud

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Re: Components you wish existed.
« Reply #202 on: October 13, 2017, 01:48:40 pm »
Passive components that combine resistance and defined inductance. We could call them reductors or some other clever name. Resistance in the 1mOhm to 100mOhm range, inductance in the nH to uH range. Example: I could order a reductor with 4.7mOhm and 330nH. Or 10mOhm with 750nH.
 

Offline Neomys Sapiens

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Re: Components you wish existed.
« Reply #203 on: October 13, 2017, 07:57:01 pm »
I know those kits. But they don't produce rotary switches as nice as the ready-made ones and they always leave out some options. Most were low-to-medium quality and had open contacts.
 

Offline alexanderbrevig

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Re: Components you wish existed.
« Reply #204 on: November 07, 2017, 08:17:24 am »
I'm going nuts looking for this.

I have a PCB with an LCD close to the front panel, and I need to have a 1/4" jack on that same panel. I can of course route out a hole for a panel mount jack and then wire it up but seem so wasteful as it's an extra manual (expensive) step in assembly.

Online blueskull

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Re: Components you wish existed.
« Reply #205 on: November 07, 2017, 08:25:32 am »
ARM Cortex A with relatively large co-packaged RAM without needing to sign NDA (unlike Samsung/Qualcomm phone PoP chips). ETH PHY, USB PHY and PMIC integration is also welcomed.
Something like AllWinner v3s with larger RAM and more beefy CPU (say, quad A7 or quad A53), preferably in 0.8mm or larger pitch BGA.
In other words, OSD3358 with a modern CPU core and a Chinese price.
 

Offline RES

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Re: Components you wish existed.
« Reply #206 on: November 07, 2017, 08:29:04 pm »
3 mm RGB LED with four leads at the bottom (not in one line, but one on each "corner", in square) of the dome and without edge (with a dot for cathode/anode indication) Can only find these 3 mm RGB LEDs with the leads in line and without round shape.
« Last Edit: November 07, 2017, 08:52:19 pm by RES »
 

Online technix

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Re: Components you wish existed.
« Reply #207 on: November 09, 2017, 07:44:42 am »
3 mm RGB LED with four leads at the bottom (not in one line, but one on each "corner", in square) of the dome and without edge (with a dot for cathode/anode indication) Can only find these 3 mm RGB LEDs with the leads in line and without round shape.

Surface mounted ones may work.
 

Offline ikrase

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Re: Components you wish existed.
« Reply #208 on: January 02, 2018, 06:00:56 am »
- Plated through hole edge connector proto board for an economical price. (I may just end up having this manufactured. Vectorboard Plugbords cost at least 25 dollars each, but the cheapest fabs I know of will make them in quantity 100 for under 5 dollars a board, I think.)

- Cheap tightly regulated 24 volt DC/DC supplies with 10 kV isolation. Something with some of those features exists, just not all of them. Have actually ended up deciding to buy stacks of cheap DIN rail supplies, which have 3 kV isolation, instead. May end up going to 60 Hertz Hell.


- <10 femtoampere leakage current gas discharge tube voltage limiters

- 1 kilovolt high speed (but stable at unity gain and DC) op-amps.

- Actually good high-current-output op-amps

- Cortex M4F microcontroller, in DIP package, with built in USB and JTAG, and with minimal GPIO but a high-speed/high-bandwidth/moderate-distance bus (multiple lines of high-speed RS485 maybe?), and the ability to connect to arbitrary IO modules also in DIP package (UART, SPI ,I2C, GPIO, 8-bit sub-processor, small patch of FPGA fabric, etc).  Kinda like a modular PLC, but for much lower-level software and hardware.

- Single chip, non-tiny-package, military temperature range multi-cell complete Li-ion charger/controller unit that handles the complete combo of: Cell protection, high speed charging, trickle (solar) charging, gas gauging, and output disconnect. I am amazed that Sparkfun does not sell any such device.


- Automagical tri-state bidirectional output buffer / input limiter / level shifter / isolator pack.

- Lithium battery packs with similar market penetration to the AA battery

- A truly rail-to-rail op-amp (maybe with internal charge pump...)

- Spray-on IP65 Rating for switches and connectors

- Ceramic or PEEK UHV compatible Mini DIN connectors. (Something similar does exist, the "Sub-C" connector, but very expensive, overly complicated w/ crimp pins, and rather bulky.)

- Peltier modules with efficiency befitting a solid-state device.

- MLC protoboard

- A material that has the consistency of modelling clay when supplied but hardens into a polymer with temperature and outgassing properties similar to PEEK. (I made something like this by mixing Loctite/Hysol 1C epoxy with powdered plaster-like ceramic potting compound. It kinda worked.)

- Room Temperature Vulcanizing Viton rubber

- Paint-on / Dip-on Thermionic Cathode Coating. I know that something approaching this existed in the heyday of vacuum tubes, but supposedly it didn't work very well.
 

Offline BrianHG

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Re: Components you wish existed.
« Reply #209 on: January 02, 2018, 07:15:08 am »
- A truly rail-to-rail op-amp (maybe with internal charge pump...)
tidu018 < at least for the GND side.

As for your other opamps, check out apexanalog's PWM opamps for high current, but is costs big $.
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Online blueskull

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Re: Components you wish existed.
« Reply #210 on: January 02, 2018, 07:36:16 am »
- A truly rail-to-rail op-amp (maybe with internal charge pump...)

OPA365
 

Offline BrianHG

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Re: Components you wish existed.
« Reply #211 on: January 02, 2018, 07:53:05 am »
- A truly rail-to-rail op-amp (maybe with internal charge pump...)

OPA365
I stand corrected...  My listed tidu018 is a reference design app note for the OPA365....  However, to achieve the true-GND with the OPA365, you need a pull-down resistor.  So, the device still gets soooo close....

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Offline Cerebus

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Re: Components you wish existed.
« Reply #212 on: January 03, 2018, 12:00:01 am »
- Plated through hole edge...
...supposedly it didn't work very well.

You forgot "a pony", and "the moon on a stick".  :)
Anybody got a syringe I can use to squeeze the magic smoke back into this?
 

Online forrestc

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Re: Components you wish existed.
« Reply #213 on: January 04, 2018, 06:20:39 am »
- A truly rail-to-rail op-amp (maybe with internal charge pump...)

OPA365

LTC1152 perhaps?  From the datasheet: "the input CMR actually extends beyond either rail by about 0.3V".   The output seems to be fairly high impedance though...   

I know there's quite a few opamps out there using various versions of this design.   Personally, I find that rail-to-rail inputs aren't all that necessary anymore since I'm mostly using opamps as buffers for ADC's, and I can pretty much always use an inverting topology which essentially eliminates the need for rail-to-rail inputs.   Rail-to-rail outputs are much more critical since most ADC's measure from ground to Vref.





 


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