Hello,
We are currently using the B524 series, but I was looking through the documentation for M404 and M524 (M-SoM datasheet | Reference | Particle) and wondering if we should start investigating it more seriously, however for the ULP sleep mode with RTC wakeup, it seems like the power consumption is almost a factor 10x of the B-series
M524
ULP mode sleep, RTC wake-up typical: 415 uA
B524
ULP mode sleep, RTC wake-up typical: 54.8 uA
Are these preliminary numbers or a somewhat realistic ballpark of what we can expect?
Hey Christian
Our gen 4 power supply is not as efficient as our previous generation - in general the chip can wake on more 'sources' but that makes the basic RTC mode more power hungry.
Device OS does allow you to add in an external AM1805 ultra low power RTC which contains a power set - we use this in our designs for about $0.60 extra to boost battery based usage into the 3 year time period as well as implement shipping mode and it works great. This chip uses about 0.17µA in sleep mode and connects via I2C. Food for thought 
Thanks
Nick.
2 Likes
The M series uses a Realtek RTL872x MCU vs. the Nordic nRF52840 in the B series. The sleep mode current for the RTL872x will always be significantly higher than the nRF52.
1 Like