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$8,567 pledged of $14,000 goal
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$8,567 pledged of $14,000 goal
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    1. Andrew Plumb on May 21, 2012

      (...and by 5.5V I really meant 5.0V)

    2. Andrew Plumb on May 21, 2012

      Just to confirm - I see in the current schematic that you have the USB D+/- hooked up to the R8C - does the firmware go through a proper enumeration process to pull 500mA instead of the 100mA default?

      Second Q/long-shot request: Have you considered replacing RV1 with a digital pot (e.g. Microchip MCP4018 - http://www.microchip.com/wwwproducts/Devices.aspx…) and using a quad-encoded "mouse wheel" or capacitive swipe zone for manual intervention?

      That would open up some options for Really Useful Features like built-in supply ramping and USB-settable/controllable interface.

      Great project! I've put myself down for an international 4-pack (aka Canada) so I can have 1.8V, 2.5V, 3.3V and 5.5V going all at once. ;-)

    3. ETONNET LLC 2-time creator on May 21, 2012

      Yes, self-powered variable power supply is a good idea. We have thought about that. Using li-ion battery and one voltage boost chip, we can reach this requirement.
      Regarding the high voltage output, yes, we will include this feature in our next version. Actually, we do have one prototype. The output voltage supports up to 25V.

      Mike and Brad

    4. James Bailey
      Superbacker
      on May 18, 2012

      Haha, thanks for your feedback feedback, I love the interactive nature of kickstarter! Well if you're after extra points, what if you made another reward that was a barebones battery box for an AA + booster circuit that could plug into the USB and make it completely self sufficient while mechanically engaging with your box? Double points for using a LiIon battery that recharges off the USB with some kind of low-batt warning! ;)

    5. Benjamin Vernoux on May 18, 2012

      A really good feature will be current limiting feature and voltage up to 9V, but anyway the hardware is already very good like that.

      Best Regards
      Benjamin

    6. David Johnston on May 17, 2012

      I used to spend a lot of time in the lab when I was a board design engineer. Now I'm a cryptographic chip design engineer, so I only occasionally go into a lab to try on my designs when the silicon comes back. One of the problems I always encounter is getting hold of useful power supplies. (1) They tend to 'walk away' if left unattended. (2) Modern silicon runs on low voltages (E.G. 0.6 - 1.3v ) and the PSU control ranges tend to very coarse relative to that range.
      The idea of having my own USB powered/controlled, voltage and current limit controllable PSU that I can take with me in my laptop back would is very exciting because it would solve all my PSU problems. I don't personally have a need for higher current or voltages, but other people might. I'd pay more for a device with independent current control since it takes an extra knob and display. Being able to control it through USB and script a bringup sequence that ramps the current until the right voltage is reached (or abort if it takes too much) would be awesome since it would be more accurate that turning the knob with my fingers.

    7. ETONNET LLC 2-time creator on May 15, 2012

      Hi James and David!

      We have discussed your suggestions and have to agree. As this is the first iteration we clearly have room to improve. At the same time, portability and cost effectiveness are key ingredients. We have started working out how to incorporate current control without adding significant costs to the build. We have also been looking at alternative housings in order to increase the portability. So James, we're going after those extra points you mentioned.

      Thanks for the feedback,

      Brad and Mike

    8. David Johnston on May 14, 2012

      I agree with the other guy. Think about independent control and display of current and voltage. This is what distinguishes a useful lab bench power supply from a useless lab bench power supply.

    9. James Bailey
      Superbacker
      on May 14, 2012

      Looks great guys! Killer features I'd like:
      - As thin as possible (pocketable)?
      - If not thin, tiny alligator clips and leads stored within device?
      - Press a button to change to Current Control (extra points for independent selection of current and voltage display and current and voltage control)

      But if it was just as it is, you have my money! ;)