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Member #612361

Member Since: October 31, 2014

Country: United States

  • As soon as the micro USB is connected, the MCP73831 generates the 4V that feeds the VBAT supply.
    So, it charges the battery and feeds the 5V DC/DC converter (TPS61200).

  • From the schematic of the breakout board, the EN pin is connected to VBATT through a 10KOhm pullup resistor.
    So, when I need to shut down the PowerCell, I draw 100s of uA from the battery through the pullup resistor forcing the EN pin to GND.
    How is that power saving?

    In comparison, the TPS61200's current drops to 1uA in shutdown mode (EN=GND) from 50uA in quiescence regime (EN=VBATT & IOUT=0A). In other words, the pullup resistor draws many times more current than just letting the PowerCell run with no load.

No public wish lists :(