A bandgap voltage reference generator includes a bandgap voltage reference circuit
and a fast startup circuit. The fast start-up circuit, which is cost-efficient
and saves power consumption, can rapidly start up the bandgap reference voltage
circuit coupled thereto. The fast start-up circuit comprises a P-channel MOSFET
or an N-channel MOSFET. Upon the bandgap voltage reference generator being powered
by an external DC voltage, the bandgap reference generator will possibly operate
in the power-down operating state. At this time there exists a large voltage drop
between the gate and the source of the P-channel MOSFET (or N-channel MOSFET),
and thus a large current flows rapidly through the P-channel MOSFET (or N-channel
MOSFET). Voltages of drains of two specific MOSFETs in the bandgap voltage reference
circuit will thus be pulled to be substantially the same, and the bandgap voltage
reference circuit is brought into a normal operating state. The output of the bandgap
reference generator is then very close to the bandgap voltage of silicon.