BLE error power consumption

[Romain]

Hi,

I use BMD-350 on NRF52832 with SDK v13.0.0

I configure my radio to run the BLE at -20dBm power through the API sd_ble_gap_tx_power_set()

But few seconds after starting advertising [ie 5 seconds] (my device is not yet connected to other device) my power consumption changes from 0.3mA to 1.2mA whereas my application doesn't change any register. But I think the SoftDevice changes configuration of  register which impacts power consumption.

Best regards,

Romain

[Sigurd]

Hi,

 

What example in the SDK are you testing?

Are you using any other peripherals?

What happens if you don’t call  sd_ble_gap_tx_power_set(-20)?

Does the power consumption change if you power cycle the device before you do the measurements?

[Romain]

I'm using only SPIS peripheral.

If I don't call the function sd_ble_gap_tx_power_set(-20): the power consumption is the same as previously.

[Sigurd]

I'm not able to reproduce this. With 1.2mA, it' sounds like the SPI peripheral and the HFCLK is running. Could you provide some example code on how you do this?

[Romain]

I find my problem it comes from the SPIS library: the SPIS_CS (chip select) is set to input pin without pull polarity so when my master is off the pni state is undefined (tristate) and power consumption increase. And its not a problem to set this pin to pull-up by default because the ECU in low-power mode doesn't consume current for this pin configuration.