| abstract |
A manner of generating internal voltages such as a high voltage, an intermediate voltage and an internal power supply voltage is switched in accordance with a power supply level setting signal (ZCMPE). When the voltage level of an external power supply voltage (EXVDD) is low, a current drive transistor (24) receiving an output of a comparing circuit and an auxiliary drive transistor (31) are forcedly set in a conductive state, and external power supply voltage is transmitted on an internal power supply line (10p). At this time, the comparing operation of the comparing circuit (23) is stopped. When the level of the external power supply voltage is high, the comparing circuit is activated down convert the external power supply voltage for generating a peripheral power supply voltage (VDDP) on the internal power supply line. Accordingly, the peripheral power supply voltage of an optimal voltage level could be generated according to the external power supply voltage level. |