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ETH-PBL / VitalCore

Self-contained, Miniaturized, BLE-enabled Embedded Platform for Low-Power, Wearable, and Hearable Applications
GNU General Public License v3.0
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Network Core Power Draw #4

Open schilkp opened 1 month ago

schilkp commented 1 month ago

Unexpected high DC power draw.

Tested with a VC with only the NRF53 soldered and powered directly via 1.8V. With the network core enabled with BLE image and app core in sleep, power draw is around 5mA @ 1.8V With the network core disabled and app core in sleep, power draw is less than 50uA @ 1.8V

Code to disable network core:

NRF_RESET->NETWORK.FORCEOFF = RESET_NETWORK_FORCEOFF_FORCEOFF_Hold;

Seems like a hardware issue related to the network core? possibly oscillator or GPIO related?

villanif commented 1 month ago

I briefly investigated if the issue could possibly be oscillator-related. In my opinion even with wrong oscillator parameters a 5mA draw cannot be explained, as a wrong oscillator setup should draw at most in the order of hundreds of uA (current can only be drawn by loading and unloading the capacitor). I guess the more likely explanation is a wrong GPIO configuration. According to the datasheet, GPIO electrical specifications, the current draw for the standard drive of the GPIO pin, the output set high, is at least 3 mA. If one grounded pin is pulled high by NRF, this would explain the data consumption.