In my application I’m using a MOSFET to cut an SD card’s 3.3v supply when it’s not in use. However, I found out that the SD card is still getting powered through the SPI lines (I measure about 2.8v on the SD card’s VCC pin, perhaps because the SPI lines can’t supply much current). Is there a way to force the SPI pins low or high impedance in Mbed?
I am using the nRF52832 chip as my MCU, and I’m using the
FATFileSystem classes to talk to the SD card. I guess I can just destroy the
SDBlockDevice instance and create some
DigitalOut pins on the original SPI pins to force them low, but I’m wondering if there’s a better way to do this.
Thank you for the help.