Data Sheet

FSC-BT806BDatasheet
Shenzhen Feasycom Technology Co.,Ltdwww.feasycom.com
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Error Mode
The charger enters the error mode if the voltage on the VCC_CHG pin is too low to operate the charger
correctly(VBAT_SENSE is greater than VCC_CHG - 50mV (typical)).
In this mode, charging is stopped. The battery charger does not require a reset to resume normal operation.
4.1.2.2 Battery Charger Trimming and Calibration
The battery charger default trim values are written into internal flash when each IC is characterised. Please
contact Feasycom regarding to PS keys.
4.1.2.3 VM Battery Charger Control
The VM charger code has overall supervisory control of the battery charger and is responsible for:
Responding to charger power connection/disconnection events
Monitoring the temperature of the battery
Monitoring the temperature of the die to protect against silicon damage
Monitoring the time spent in the various charge states
Enabling/disabling the charger circuitry based on the monitored information
Driving the user visible charger status LED(s)
4.1.2.4 Battery Charger Firmware and PS Keys
The battery charger firmware sets up the charger hardware based on the PS Key settings and call traps from the
VM charger code. It also performs the initial analogue trimming. Settings for the charger current depend on the battery
capacity and type, which are set by the user in the PS Keys.
4.2 Reset
FSC-BT806BB is reset from several sources:
RST# pin
Power-on reset
USB charger attach reset
UART break character
Software configured watchdog timer
The RST# pin is an active low reset and is internally filtered using the internal low frequency clock oscillator.
Feasycomrecommends applying RST# for a period >5ms.
At reset the digital I/O pins are set to inputs for bidirectional pins and outputs are set to tristate. Following a
reset,FSC-BT806BB assumes the maximum XTAL_IN frequency, which ensures that the internal clocks run at a safe(low)
frequency until FSC-BT806BB is configured for the actual XTAL_IN frequency. If no clock is present atXTAL_IN, the
oscillator in FSC-BT806BB free runs, again at a safe frequency.