B-WL5M-SUBG1: module draws 2 µA, but whole board ~80 µA in Stop2
Hi,
I’m running a LoRaWAN end node on the B-WL5M-SUBG1 (MB1779B), based on the LoRaWAN_End_Node_LBM example from CubeWL 1.6.0. The board is powered from a 3.6 V battery on CN5 (E3V3). SB14 is removed and the STMod+ adapter and debugger are disconnected.
In Stop2 I measure about 2 µA on JP2, so the module itself is fine. But on CN5 the whole board still draws around 80 µA.
What I’ve done so far: PA3 pull-up and PA15 pull-down (from this thread), all unused pins incl. SWD/UART set to analog, RF switch pins PC3–5 low during sleep, SPI flash in deep power-down, and all four sensors put into power-down over I2C at boot. Opening SB15 made it worse (~600 µA), I guess because the sensors get back-powered through the I2C pull-ups.
Is ~80 µA expected for this board on E3V3? Which parts are still powered from 3V3?
Thanks!