04309627 is referenced by 103 patents and cites 12 patents.

A detecting circuit for a power source voltage comprises a reference voltage generating circuit for generating a reference voltage, a voltage dividing circuit for dividing the power source voltage, and a voltage comparing circuit having one input terminal connected to receive the reference voltage from the reference voltage generating circuit and another input terminal connected to receive the divided voltage from the voltage dividing circuit. In one embodiment, the reference voltage generating circuit comprises at least two MOS-transistors having different threshold voltages and having the same polarity, one of the MOS-transistors having its gate and drain connected together with the drain being connected to the gate of the other MOS-transistor, the drain and source of the other MOS-transistor each being connected to a resistor, and the drain of the other MOS-transistor being connected to one input terminal of the voltage comparing circuit. In another embodiment, the reference voltage generating circuit comprises a P-channel MOS-transistor having its drain connected to the drain of the N-channel MOS-transistor and the gates of the P-channel and N-channel MOS-transistors being connected to the drains thereof respectively, one of the MOS-transistors being connected to one terminal of the power source, and the other of the MOS-transistors being connected to one input terminal of the voltage comparing circuit.

Title
Detecting circuit for a power source voltage
Application Number
6/24441
Publication Number
4309627
Application Date
March 27, 1979
Publication Date
January 5, 1982
Inventor
Junichi Tabata
Tokyo
JP
Agent
Bruce L Adams
Emmanuel J Lobato
Robert E Burns
Assignee
Kabushiki Kaisha Daini Seikosha
JP
IPC
G08B 21/00
H03K 17/30
H03K 5/24
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