Switching device control circuit
AssigneeON Semiconductor Trading, Ltd.
InventorsRyuji Hokabira, Takekiyo Okumura
Life of this patent
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Abstract
There is offered a switching device control circuit that can accurately estimate a temperature of a power device to execute thermal shutdown without increasing the number of terminals. The control circuit has an output unit controlling an operating current flowing through an IGBT based on an input signal, a temperature detection unit outputting a detection signal when a temperature of the control circuit rises above a second preset temperature that is set corresponding to a first preset temperature of the IGBT after the IGBT commences its operation, and an output control unit controlling the output unit so as to turn off the IGBT in response to the detection signal.
Claims7
A control circuit of a switching device comprising:
- an output unit controlling an operating current flowing through the switching device based on an input signal;
- a pre-operation temperature detection unit detecting a temperature of the control circuit before the switching device is put into operation;
- a temperature detection control unit outputting a first detection signal when the temperature of the control circuit rises above a second preset temperature after the switching device is put into operation and being configured to be capable of modifying the second preset temperature in accordance with a result of detection performed by the pre-operation temperature detection unit, the second preset temperature being defined corresponding to a first preset temperature of the switching device;
- and
- an output control unit controlling the output unit so as to turn off the switching device in response to the first detection signal.
Dependencies are inferred from the claim text.