problems with digital mems microphone configuration

[sonydw-admin]

Hello, I am trying to change the configuration on the extension board to use digital microphones. After I make the hardware changes (I have shorted the jp14 and r49, and removed r50) it seems that the extension board is broken. I have been using the SD card, which no longer works, and if I plug my usb cable into the extension board, it's not recognized. The main board works as expected, but can no longer find the SD card, and it does not seem to power the extension board when i measure with a voltmeter. When I power with the extension board usb, the voltage is as expected most places but around 1V on the 1.8V pin.

Ive verified that the voltage is the same on both sides of my added resistor and continuity where expected. I have done this twice with two different extension boards and gotten the same output.

What am I doing wrong?
Is it safe to try to power using two usb's?

[CamilaSouza]

Hello!

Would it be possible for you to send us a picture of how your modifications look like?
Also, did you separate the boards during the soldering process?

To test if the problem is on the main board or the extension board, could you separate the boards and test the voltage of the main board in the EXT_VDD pin (pin 3 of connector JP2)? It should be around 3.7V ~ 4V.
Then connect the boards again, without externally powering the ext. board with USB, and check the voltage in that same pin of the main board. Is there a significant drop?

After that, another thing we could check is if the voltage regulator of the extension board is working properly. To do that, test the 3.3V and 5V pin of the JP3 connector on the ext. board. This 3.3V is the line that powers the SD card, so we need to check the voltage there.