G120H and PowerState.Sleep

NETMF & Gadgeteer
1

Hi,
We have just tried the Power state.sleep on a G120H loaded with 4.3.5.0, the real time clock awake nicely the card when the time slice is elapsed.

PowerState.Sleep(SleepLevel.DeepSleep, HardwareEvent.OEMReserved2);

In full power we seek 120 mA from the 3.3V power supply, during DeeepSleep 18 mA, that current drain seems a bit high especially if we compare with VBAT and the few µA drain of the RTC.

As 18mA is a high current drain to be able to run continuously from a battery, have you an idea to get a lower drain during our long sleep period ?

The module must be awaked twice a day for 2 minutes to sequence I/O ports. The system should run from a battery pack for a month.

using a 1200 mAH battery pack is the target, 1 mA Sleep drain will be perfect

Regards
Loïc

2

hi Loïc, nice smith chart avatar.

You can use the power off mode to get down to about 5mA, but wake is like a reset so your application starts from scratch. My theory is that the 18mA is used to refresh the RAM, but that’s just guessing.

https://www.ghielectronics.com/community/forum/topic?id=16365&page=4

3

Thanks,

I will have a try with SleepLevel.Off

Mesured current 4.6 mA and the system is making a cold start after each elapsed period so I am loosing the USB debug.

I suppose that this figure is the minimum atainable.

To improve the overall consumption, i have to find some external trick to shut down the power supply during the requested sleep period.

Loïc