Seeed XIAO BLE Sense nRF52840 deep-sleep mode

[msfujino]

Hi Vint1k,
Please read the link below.

Sleep Current of XIAO nRF52840, Deep Sleep vs. Light Sleep

I compared the sleep current between SystemOFFSleep(DeepSleep) and SystemONSleep(LightSleep). The board service package is “Seeed nRF52 Boards 1.1.1”. To enter sleep mode, I used NRF_POWER->SYSTEMOFF = 1; for DeepSleep and RTOS delay() function for LightSleep. The pppk2 was used to measure the sleep current by applying 3.6V to the BAT pad on the backside of XIAO. The measured results were 2.4uA and 5.4A, with no significant difference. Note that the quiescent current of the 3.3V LDO is measure…

System_ON_Sleep of XIAO BLE

System_OFF_Sleep (Deep Sleep) is used to significantly reduce current consumption, but requires an external trigger for wake-up. On the other hand, System_ON_Sleep can easily woken up using the built-in RTC interrupt. In a project that periodically sends data from a peripheral to the central, I experimented with System_On_Sleep to see how much current consumption of a peripheral XIAO could be reduced. In System_ON_Sleep, the CPU sleeps by the WFI() command, but during sleep, it seems to repeate…