Patent attributes
Disclosed herein is a block switch of a flash memory device in which a voltage higher than a predetermined operating voltage is generated to drive path transistors in order to stably apply the predetermined operating voltage to a selected cell block of the flash memory device. The block switch generates a high voltage clock signal of a high voltage level according to a control signal and a clock signal, and raises the voltage level of an output terminal to a predetermined level according to the high voltage clock signal. Accordingly, a high voltage can be outputted even at a low power supply voltage. There is no need for a decoder for high voltage as in a precharge and self-boosting mode. A voltage can be directly applied to word lines without a precharge operation. It is thus possible to reduce an operating time.