High voltage withstanding circuit and voltage level shifter

摘要

A switch circuit having a high withstanding voltage and low driving ability and another switch circuit having a low withstanding voltage and high driving ability are connected to a specified node in parallel. When discharging the charges of the specified node, the switch circuit having the high withstanding voltage is turned ON and the switch circuit having the great driving ability is then turned ON. Accordingly, it is sufficient that only the transition of the logical voltage of a switch circuit having the high withstanding voltage is taken into consideration to set the ON timing of a switch circuit having the high driving ability. Consequently, timing setting can be performed easily. After the switch circuit having the high driving ability is turned ON, a discharge path for the charges of the specified node takes two paths which passes through both switch circuits in parallel. Consequently, an operating speed can be increased.