|
|
Battery Monitor driver implementation for the LPF3 family.
============================================================================
The Battery Monitor driver on LPF3 is a part of the battery monitoring system in the Always On domain (AON). It periodically takes measurements of the supply voltage of the device and will issue interrupts if the configured upper limit or lower limit is crossed.
The battery monitoring system on LPF3 has a resolution of 1/256 V (around 3.91 mV). The BatteryMonitor_getVoltage() function will round the voltage to the nearest mV. For example, if the supply voltage is measured to be 2003.91 mV, then BatteryMonitor_getVoltage() will return 2004.
The supply voltage measurement remains active in standby power mode. The interrupt used by the battery monitor module is capable of bringing the device out of standby and into active mode to handle it. That means that an application will not miss a change in supply voltage just because the device has transitioned to standby power mode. While in standby, the supply voltage will only be sampled during a VDDR recharge pulse. This means that the sampling frequency in standby will be determined by the temperature as leakage increases with temperature and requires more frequent recharging of VDDR.
