marcoreps
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More OSMMU* details
🕑 Added 2018-01-31 21:55:02 +0000 UTC * Open Source Multi Measure UnitThis title is a reference to Keithleys elusive source measure units. I have tried to get another one forever and now I'm just making my own, much better version instead :)
Keithleys regular SMUs are precision power supplies with pA resolution and 4-quadrant capability meaning they can be programmed to source and measure +/- voltages and +/- currents. Almost nobody needs pA resolution, so I wont include that initially, but a 4-quadrant supply is very useful. Three 4-quadrant supplies are even more useful!
And that's what I want to make: A digitally controlled 4-quadrant PSU with 3 isolated channels. Here are some of the possibilities of such a device:
- A single channel can be a normal adjustable psu
- With the current sink capability it can discharge and analyze batteries and capacitors
- It can analyze other 2 pin components and act as a curve tracer
- I'm trying to use HF components, maybe it can even be an antenna analyzer, transmitter etc? Low priority for now ...
- A second channel enhances the possibilities greatly:
- Channels can be stacked to get a higher voltage output channel
- Now even transistors and thyristors can be analyzed
- 2 Phase stepper motors can be driven and tested with clean current waveforms
- Can analyze a 2s pack or 2 batteries at the same time
- Can output waveforms on one channel and measure result on the other channel. Is that what's called a network analyzer?
- I-V characterization of solar cells
- Diminishing returns for the third channel:
- Analysis and driving of 3-Phase brushless motors
- Classic 3-output PSU arrangement
It is a complicated design for sure and I haven't even started to think about the software that controls it all. But then again there is afaik no other product like it, so it is worth it. The more I think about it, the more application ideas appear ... Please comment if you have any :)
Comments
That sounds exciting - really looking forward to it!
David W DeVillers
Looking forward to this. I am a nubee and power supplies interest me a lot. Thank you!
ulf karlsson
Wow. This could be really interesting!
Marco Reps
Same here :)
Marco Reps
Interesting idea to accomplish that: Could use a very efficient switching supply dynamically set close to the programmed output voltage and a classic linear regulator dropping only the last few volts for low ripple and immediate response
Marco Reps
Well if nobody else does it ... :)
Holger Scade
Looking forward to see the first attempts. *excited*
Rick Mann
High power, please :)
John McCormick
Giving Keithley a run for their money.
