SEMICONDUCTOR INTEGRATED CIRCUIT

摘要

PURPOSE:To obtain a fixed internal power supply voltage lower than an external power supply voltage by controlling the gate of a voltage converting MOSFET in accordance with a reference voltage. CONSTITUTION:An EPROM41 is provided with external power supply terminal 42, 43 and an internal power supply terminal 44. The source and drain of a MOSFET51 converting a voltage Vp to be supplied to the terminal 43 into a voltage Vpp lower than the voltage Vp is inserted between the external power supply terminal 43 and the internal power supply terminal 44. A reference voltage generating circuit 54 is connected between the terminal 43 and the earth. A control circuit 58 controls the gate of the FET51 in accordance with the reference voltage Vref of the generating circuit 54. Consequently, the voltage Vpp of the terminal 44 is lower than the voltage Vp and is always set up to a constant value. Thus, the fixed internal power supply voltage lower than the external power supply voltage can be obtained.