How to reduce power consumption for 4ms interval

[Nobuaki]

Hello,

I will post this question to NDZ first time .

Our customer is in trouble to reduce power consumption at nRF52832. Our enviornment is below.

CPU: nRF52832 SoftDevice : S132 v2.0.1 SDK : nRF5 SDK v11.0.0

We stop advertise and scan during idle time, however, observed the attached peak currency every 4ms interval. We enable gpio and uart. Please refer to the attached excel file.

ComsumptionCurrecy4ms.xlsx

There are peak currency every 4ms interval in the attached file and we doubt it is caused by gpio polling in Softdevice. Is it correct ?

If so, are there any methods to extend polling interval in Softdevice? Our customer eagarly wants to reduce the power consumption.

Thanks for your following up.

[Stian Røed Hafskjold]

These spikes are probably refresh mode spikes. Please see these posts:
devzone.nordicsemi.com/.../ devzone.nordicsemi.com/.../

So in your measurements you have 13 µA in IDLE between the radio events. The expected IDLE current when no peripherals are running, other than what is needed by the SoftDevice, is 2 µA. This includes the spikes you are seeing. Please verify this by measuring on an unmodified example from the SDK. For example the app_pwr_profiling (turn off logging).

I believe your measurements are the result of two things; I get the exact same measurements with this setup:

1. The range of the power analyzer is set to 100mA or something like that? This range will not be sufficient when measuring the 300nA current between the spikes. The range needs to be set to "auto", so that it switches between µA and mA range, because of the spikes (µA range only will just cut of the spikes). If you do not have "auto" on your equipment I don't think you can use it to measure the IDLE current. Use an ampere-meter instead.

2. GPIOTE IN event is enabled on one or several of the pins. Please see this errata: infocenter.nordicsemi.com/.../anomaly_832_97.html