Overheat protection circuit and semiconductor device including the same
AssigneeAblic Inc.
InventorKaoru Sakaguchi
Life of this patent
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Abstract
An overheat protection circuit includes a first constant current source which supplies a first constant current to a temperature sensitive element, a first transistor provided between the temperature sensitive element and the first constant current source, an output current detection circuit which controls a gate voltage of the first transistor by a voltage based on a sense current corresponding to an output current of a semiconductor device, and an output circuit which supplies an overheat detection signal based on a result of comparison between a temperature sensitive current and the first constant current.
Claims4
An overheat protection circuit configured to protect a semiconductor device from overheat, comprising:
- a temperature sensitive element configured to make a temperature sensitive current corresponding to a temperature of the semiconductor device flow;
- a first constant current source configured to supply a first constant current to the temperature sensitive element;
- a first transistor provided between the temperature sensitive element and the first constant current source;
- an output current detection circuit configured to control a gate voltage of the first transistor by a voltage based on a sense current corresponding to an output current of the semiconductor device;
- and
- an output circuit configured to supply an overheat detection signal based on a result of comparison obtained by an inverter circuit having an input terminal connected to a connection point between the first constant current source and the first transistor, wherein the inverter circuit compares the temperature sensitive current and the first constant current.
A semiconductor device comprising:
- an output transistor containing a gate;
- a drive circuit configured to supply a control voltage to the gate of the output transistor;
- and
- the overheat protection circuit according to claim I configured to control a gate voltage of the output transistor in accordance with the control voltage of the drive circuit.
Dependencies are inferred from the claim text.