Current pulses appear in power off mode - NRF52832

[keithauhk]

Hello,

I am using the nfc_system_off example code to evaluate the characteristics of power off mode.

Current measurement is done by following the instruction shown in this page:
Current measurement guide: Measuring current with PCA10040 v0.9.0

I am working with a PCA10040 v1.1.1. I make use of a current measurement dongle between the pins of P22 to power off current consumption.

While looking at the current waveform, I found some current pulses up to 70uA that appears ~every 0.19s.

I would like to confirm:
1. Are these pulses expected? Would those pulses related to the debug chip on PCA10040? Or are those pulses caused by the internal DC DC regulator?
2. Is there any room to further reduce power off mode current based on the nfc_system_off example?

Thank you!

[Vidar Berg]

Hello,

The regulators have a refresh mode used in low power modes which results in short recharging spikes. The average current should be around 600 nA, are you able to measure that? You can also use a simple ammeter to measure the average sleep current.

Best regards,

Vidar