Hi,
using the MKR NB 1500 I assumed I could boost 5V to the 5V pin when in battery mode with USB cable detached. For this, the I2C-controlled switcher charger/boost converter BQ24195L can be programmed. See example code Arduino_BQ24195/PMIC Boost Mode and respective lib, code line with "PMIC.enableBoostMode();"
However, in battery mode, I can only measure 2V7 at the 5V output. On the other side, I measured an unexpected 5V at the VIN pin, which should not be there due to the pull-down resistor (1MOhm, R19). When I assist this pull-down with pulling VIN to GND with an additional 220kOhm resistor, the 5V1 appears instantaneously at the 5V output pin.
I found this to happen on both of my two boards with nothing else but the battery connected (charged at 3V9).
My question is if this is indented behavior and should I consider this additional pull-down in the circuit or is there something else I miss?
Any help is appreciated. Thanks
bst Matthias
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