| 摘要 |
PURPOSE:To stabilize operation eliminating noise and fluctuation of power supply by a method wherein an internal functional circuit composed of MOS transistor is operated under a voltage supplied from an internal power supply circuit and other voltage from the first or second terminal. CONSTITUTION:An internal power supply circuit 30 with a control terminal 31 is provided between a power supply terminal 10 and an internal functional circuit 50. The internal power supply circuit 30 is composed of a step down circuit 32 and a voltage detecting circuit 33 detecting the voltage of an internal power supply line 40 by a specified threshold value to supply the terminal 31 of said step down circuit 32 with the detected output. Through these procedures, the circuit 30 supplies the circuit 50 with VINT as power supply voltage lower than a voltage Vcc supplied for the terminal 10 to stabilize operation under wide range of externally supplied power supply voltage. |
