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  • Author Author: Jan Cumps
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USB Programmable (electronic DC load) Test Equipment

Jan Cumps

, and I are designing a programmable electronic load, here on element14: Programmable Electronic Load

We'll never make it in time for the DIY Test Equipment initiative (we may have a first prototype In the Year 2525). But it can help you if you want to build a device that can be automated with LABView or similar*.

 

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What's in the current version:

- working firmware with a SCPI integration. Complies to SCPI standard out of box.

- tested PCB with several ADC and DAC channels, programmable and readable via SCPI - isolated and with a voltage reference

- LCD interface

 

Our goal is to extend Peter Oakes' popular DC Load into a programmable one. The modular design of the control logic is a start point for other designs too.

You can adapt the ADC/DAC design and control your own instrument with it. In it's current state, it can be turned into a programmable meter, signal generator, sampler.

With firmware adaption you can link the SCPI commands with your microcontroller's timers and use it as a PWM generator or a frequency counter.

With additional hardware you can buffer in-and outputs, create a programmable power supply, ...

 

 

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Both PCB and firmware - although based on TI-RTOS for MSP432 and BoosterPack pinout, can be adapted. We've taken care that no license stops you from doing whatever you want and sources are attached.

Hope to see it reused in an element14 DIY Test Instrument.

 

 

* or other programs that support serial comms - even a plain terminal program like PuTTY.

  • in reply to jc2048

    Jon Clift wrote:

     

    ... [I don't know why you didn't use the SOIC, it would have made the assembly easier too.] ...

    For personal learning (and because I ordered the wrong part at TI store and adapted the board to that).

    That's also why I placed the components so ridiculously close to each other. I wanted to check how small I could design this.

    In the future I plan not to go smaller than TSSOP.

  • "You have until September 14th, 12:00 AM CDT to submit your completed project!"

     

    You're a real pesssimist, Jan - we've got plenty of time for the DIY Test Equipment. Peter's circuit works ok, it just needs a bit of tweeking here and there. Don't worry, we'll get you to the finish line in time.

     

    Having said that, I've stalled on building your board. When I ordered the parts, Farnell thought they had one of the voltage reference chips in stock. When I got the delivery, it turned out they were wrong and the part is on back order - they're currently predicting November. [I don't know why you didn't use the SOIC, it would have made the assembly easier too.] You've just reminded me that I was supposed to be looking around to see if I could find somewhere else to buy it from or a substitute part.

  • OK, OK, I get the hint, time to get it moving again image