GSENSOR_3V3 voltage drop

Sven Rebhan odinshorse at googlemail.com
Sun Aug 23 20:06:42 CEST 2009


2009/8/23 Christoph Mair <ml at chonyota.net>:
> The voltage is now between 3.32V and 3.44V which seems to be ok,

Nice.

> but after
> suspending it still drops to 2.44V Vmax and 1.78V Vmin (when the compass chip
> starts a measurement).

Just to make sure I got you right: You enable the "g-sensor" and get about 3.3V,
then you suspend and _while suspended_ you get 2.4V and 1.8V respectively?
What happens when you resume? Do you get back 3.3V? If this is the case you
probably don't set GPD12/13 (CS), GPG7 (CLK), GPG6 (MOSI) to 0 and GPG5 (MISO)
to pulldown during suspend and leak the voltage from the CPU. Can you please
make sure you set those pins during suspend!

Sven



More information about the hardware mailing list