| 摘要 |
PURPOSE:To prevent the gate insulating film of a MOS transistor TR from being polarized and to stabilize the operation of a semiconductor integrated circuit device by providing a diode which clamps the gate input voltage of the CMOS TR of the input circuit of a digital circuit part to the current voltage side on the side of the digital circuit part. CONSTITUTION:An analog/digital mixed type semiconductor integrated circuit device is provided with the digital circuit 1 as the 1st circuit part and an input circuit part 1a composed of a CMOS TR, and the 1st circuit part is operated at a specific voltage of 5V as an operating source voltage Vdd-Vss. Further, a linear circuit part 2 as the 2nd circuit part and an output circuit part 2a on the side of the circuit 2 are provided and this 2nd circuit part is operated at a specific voltage of 12V as an operating voltage Vcc higher than the voltage Vdd-Vcc. The diode D1 for gate input voltage clamping is connected between the connection point between the output circuit part 2a of the 2nd circuit part and the input circuit part 1a of the 1st circuit part and the voltage Vdd. Then input voltages to TRs M1 and M2 of the input circuit part 1a are clamped to prevent the gate insulating film from being polarized.
|
