Does RSL10 evaluation board have dc voltage available to power and external microphone

I would like to hook a digital PDM microphone to the RSL10 evaluations board.
Is there a dc output voltage available on the RSL10 evaluation board that could supply tens of microamps at between 1.6 and 3.6 volts, and, if so, which pad/node is it?

@dpreves

Information is in our RSL10 Evaluation and Development Board User’s Manual

There are several external power supplies available on your Evaluation and Development Board.
The user can also access signals on various headers on boards, as described throughout this document.
The external power supplies available for QFN boards
are:
• VBUS, 5 V from USB connection − available only
when USB is plugged in
• V3.3, 3.3 V from LDO − available when regulated
supply is selected
• VEXT, (P5 header) unregulated external supply −
available when unregulated supply is selected
• Battery (J5 Battery Holder, 12 mm coin cell battery

So to get 3.6V or 1.6V precisely you would need to use down- conversion e.g . via LDO’s from voltages which are available on the RSL10 board.

Power supply schematic:

PCB drawing:

Thank you for the quick answer, Martin.

The microphone I have will run from a d.c. supply of 1.6 to 3.6 v, so 3.3.v will work.

But, I am not sure that I understand your email below; i.e., can I get 3.3v from LDO with the USB cable connected to my computer?

If I want to run the DMIC Dual mic pre-programmed PACK with the RSL10 evaluation board, don’t I have to have the evaluation board connected via USB cable to my computer?

If that is not the case, would I initially connect the evaluation board to the computer via USB to download the firmware into the evaluation board?

How do I tell when running the IDE workspace when the code is downloaded into the evaluation board?

Then, after the firmware is downloaded to the RSL10 evaluation board, could I unplug the USB cable and use a 3v Li-Ion coin cell battery – which may be the easiest solution to power both the digital microphone and evaluation board.

Is that the correct thinking?

@dpreves

But, I am not sure that I understand your email below; i.e., can I get 3.3v from LDO with the USB cable connected to my computer?

If I want to run the DMIC Dual mic pre-programmed PACK with the RSL10 evaluation board, don’t I have to have the evaluation board connected via USB cable to my computer?

If your power supply configuration on RSL10 board is for stand alone USB, you need to have board powered via USB cable.

image

If that is not the case, would I initially connect the evaluation board to the computer via USB to download the firmware into the evaluation board?

See RSL10 getting started guide page 14.

" Once the updates to the configuration are completed, make sure that the Evaluation and Development Board is connected to the PC via a micro USB cable, and click Debug. J-Link automatically downloads the blinky sample code to RSL10’s flash memory."

How do I tell when running the IDE workspace when the code is downloaded into the evaluation board?

Your console will show you end of the build process. Press RST button on the RSL10 board. If you chosen CMSIS blinky example , green LED will start blinking every second.

image

Then, after the firmware is downloaded to the RSL10 evaluation board, could I unplug the USB cable and use a 3v Li-Ion coin cell battery – which may be the easiest solution to power both the digital microphone and evaluation board.

Yes you can unplug your USB cable and change jumpers on RSL10 for V_bat ext,. powered. You will find your battery voltage at the VDDO pin on RSL10.

image

Thanks again Martin,

3 Likes