I have just been measuring the power consumption of the Stalker and trying to get it even lower in sleepmode. First I tried with the POWER_TF jumper set to VCC and measured about 600uA in sleepmode. I then swapped the POWER_TF jumper to CTL_D4 to try and cut the power to the SD card during sleep but I am still getting 600uA.
Could I ask SeeedStudio to publish a low power guide to hardware and code for Stalker please, this would explain all the options available to get the power consumption down to a minimum.
In the meantime… would it be possible to explain how to use the POWER_TF jumper in CTL_D4 mode with a code example please. I think I am right in saying that the digital pin 4 can be used to switch power on and off to the SD card power regulator U6 so setting D4 to output and Switching D4 High before writing to the SD and D4 LOW when sleeping should work… when I do this I get a much hight power consumption of 40mA?