the fp9931 offers a compact power supply solution to provide all voltages required by epd panel. the fp9931 includes 2 high performance dc-dc converters, one is for positive voltage and the other is for negative voltage used by epd drivers, a vcom buffer (unity-gain opa), a positive charge pump and a negative charge pump to provide adjustable regulated output voltages.
the converters provide the regulated positive and negative supply voltage for the panel source driver ics.
the positive charge pump controller provides regulated epd gate-on voltage. the negative charge pump controller provides regulated epd gate-off voltage.
accurate back-plane biasing is provided by a linear amplifier and can be adjusted either by an external resistor or the i2c interface. the vcom driver can source or sink current depending on panel condition. for automatic vcom adjustment in production line, vcom can be set from 0v to -5v with 8 bit control through the serial interface.
the fp9931 provides precise temperature measurement function to monitor the panel temperature during operation.