charge up a dead battery

RE: charge up a dead battery

Stian Røed Hafskjold — Wed, 26 Oct 2022 14:21:40 GMT

Hi Jiyeon,

Looking at the plots I believe the VDD rise time is too slow. The maximum allowed rise time according to the specification is 60ms:

Important: The on-chip power-on reset circuitry may not function properly for rise times longer than the specified maximum.

Best regards,
Stian

JIYEON — Thu, 20 Oct 2022 03:14:30 GMT

Hi helsing,

I used custom board, which is based on nRF52832.

Our HW engineer reproduced error with power supplier.

And he said it might not relevant with specific battery model.

The test sequence is like below.

Voltage is goes up slowly, because battery will recharged slowly too.

nRF52832 is supplied 2.8V through LDO.

In similar situation, It works fine sometimes and not work sometimes.

reset pin, power pin and SPI CS are measured.

If it works fine, SPI communication will be done periodically.

Voltage was set to 1.5V and then 1.6V, 1.7V.

It starts work properly at 1.7V.

In similar situation, It doesn't work even at above 2V.

helsing — Tue, 18 Oct 2022 08:29:02 GMT

Hi Jiyeon,

Which board is this? And exactly which batteries are you using?