3.13. BATTERY
The
DuinoMite
and
DuinoMite-Mega
have a built-in LiPo battery charger and the hardware is
designed to allow them to run in low power mode for battery operation.
USB-FAULT is connected to RG7 to allow the firmware to be aware that it is running on battery
instead of an external power supply. If USB-FAULT is read as 0 the board is powered by battery.
The battery charge state can be monitored by measuring the power supply on BAT port RB2.
The Lithium Polimer battery is connected via the R31/R29 voltage divider (0.319727891) to RB2 port
as RB2 can handle a maximum voltage of 3.3V but the battery voltage can go up to 4.2V when
completely charged.
DM firmware adds PIN(21) analog input pin which could be used for Battery voltage monitoring. Note
that voltage is sensed through voltage vivider as PIC32 inputs can't measure more than 3.3V while Li-
Po battery voltage may go up to 4.2V when completely loaded. This is why the measured values from
PIN(21) should be multiplied by the magic number 3.13 to get the real battery voltage.
Summary of Contents for DuinoMite
Page 27: ...4 SOFTWARE...
