The wake-up time from STOP2 to RUN mode is longer than expected on STM32WB55.

[Ksaha.1]

Hello,

I am trying to develop an application with STM32WB55 that checks the sensor status every 500ms and goes into power saving mode set as STOP2.

The datasheet mentions that the wake up time is only about 6us. So I expected the wake up time to be very optimized. But with the test and power measurement, I get a total wake-up time of about 250us (shown in chart 3), which is very long. I tried several clock configurations to get the most optimized power consumption possible.

The measurements are made with the X-NUCLEO-LPM and the STM32Cube Monitor-Power Tool.

Do you have any idea how to reduce it?

[Remy ISSALYS]

Hello,

How do you measure the wake-up time, between which instructions? Are you using the low power manager as in STM32CubeWB example like in BLE_HeartRate?

Best Regards