Overvoltage protection circuit of output MOS transistor
First Claim
1. An overvoltage protection circuit for a circuit of an output MOS transistor and a load connected in series between a first power supply and a second power supply, comprising:
- a dynamic clamping circuit connected with said gate of said output MOS transistor;
a control switch connected between said first power supply and said dynamic clamping circuit; and
a serge detecting circuit which monitors a voltage of said first power supply and turns on said control switch when the voltage of said first power supply increases to a voltage higher than a predetermined voltage.
3 Assignments
0 Petitions
Accused Products
Abstract
An overvoltage protection circuit is for a circuit of an output MOS transistor and a load connected in series between a first power supply and a second power supply. The overvoltage protection circuit contains a control signal circuit, a dynamic clamping circuit, a control switch, and a serge detecting circuit. The control signal circuit is connected between a gate of said output MOS transistor and said load, and the dynamic clamping circuit is connected with said gate of said output MOS transistor. The control switch is connected between said first power supply and said dynamic clamping circuit and the serge detecting circuit which monitors a voltage of said first power supply and turns on said control switch when the voltage of said first power supply increases to a voltage higher than a predetermined voltage.
-
Citations
9 Claims
-
1. An overvoltage protection circuit for a circuit of an output MOS transistor and a load connected in series between a first power supply and a second power supply, comprising:
-
a dynamic clamping circuit connected with said gate of said output MOS transistor;
a control switch connected between said first power supply and said dynamic clamping circuit; and
a serge detecting circuit which monitors a voltage of said first power supply and turns on said control switch when the voltage of said first power supply increases to a voltage higher than a predetermined voltage. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A method of protecting an output MOS transistor, wherein said output MOS transistor and a load are connected in series between a first power supply and a second power supply, and a series circuit of a control switch and a dynamic clamping circuit is connected between said first power supply and a gate of said output MOS transistor, said method comprising:
-
monitoring a voltage of said first power supply;
turning off a control switch when the voltage of said first power supply increases to a voltage higher than a predetermined voltage. - View Dependent Claims (8, 9)
-
Specification