Originally Posted by Bill Glover
So ... I finally got around to playing with this step up/down voltage regulator:
The aim was to provide a constant voltage for the camera from the flight cell of a micro quad, so I could lose the #11's internal battery.
Having removed the battery the first test was to try powering up the camera from pins 4 & 5 of the USB socket (per the 'special' cable). No luck, couldn't get the camera to come on
OK so the 5V output from the regulator is a bit high to push into the battery connections on the board, but what the heck. Success ... nothing caught fire, did a 10 minute (approx.) recording without any issues. Camera processor chip was warm but no more than usual as far as I could tell. No sign of interference/noise from the regulator on the video.
So I've got the regulator mounted on the camera board now with thin double-sided foam tape, and a flylead (with a micro plug/socket joint) running out to connect to the quad. Weight of the camera in this form is 7.1 grams.
Need to arrange some packing/padding to give a flat surface to the camera so it can be mounted level (probably thin EPP or Depron sheet carved away to clear the USB socket, micro SD holder, etc.), and secure the lens module. Plus a little clear tape for insulation. Then it'll be time to give it a try in flight
As you have found out, unlike the #16, you can't use USB power without the internal battery connected. However, you should beware of using 5V applied directly to the battery. It will work, but the question is for how long. You are definitely stressing the components. Maybe you should consider putting a small diode in series with the positive lead. This will reduce the voltage to a safer level and as a side effect you will benefit from reverse voltage protection.
I received a #11 from a user which had been very badly damaged by supplying over voltage. Even the DRAM chip was destroyed.