Process deviation influence resisting over-temperature protection circuit

Abstract

The invention discloses a process deviation influence resisting over-temperature protection circuit. The circuit comprises a reference voltage input buffer stage, a resistor voltage division array, a negative temperature coefficient voltage branch circuit, a comparator and an output shaping circuit, wherein input reference voltage is buffered by the reference voltage input buffer stage to form reference voltage free from load influence; the reference voltage is divided by the resistor voltage division array so as to produce temperature setting voltage; the temperature setting voltage is output to the comparator, and is compared with voltage produced by the negative temperature coefficient voltage branch circuit in the comparator so as to produce a control signal; and the control signal is shaped and output by the output shaping circuit. The process deviation influence resisting over-temperature protection circuit can eliminate the influence of process deviation in the manufacturing process of an integrated circuit, accurately produces an actuating signal at a preset temperature point to control to switch off a protected circuit or an auxiliary circuit thereof, and realizes the over-temperature protection of the circuit.

Description

technical field [0001] The invention relates to an over-temperature protection circuit, in particular to an over-temperature protection circuit in an analog integrated circuit which can detect the temperature of the circuit and provide protection when the operating temperature is too high. Background technique [0002] Some integrated circuit products such as power supplies and drive devices often face problems such as high operating temperature and excessive heat generation, which cause the circuit to fail to work normally or even burn permanently. This requires the integration of an over-temperature protection circuit into the circuit. The function of the over-temperature protection circuit is to monitor the operating temperature of the circuit, output a control signal after the operating temperature of the integrated circuit reaches the set value, complete functions such as shutting down the circuit and power supply, and protect the circuit. [0003] The working scheme of...

AI Technical Summary

Problems solved by technology

In such a case, the potential of the node 102 set by R11 and the current source 12 may also have a large deviation, so that the protection circuit cannot output the control signal at the designed temperature point, and may only operate at an extremely high temperature. Or the case of early action at normal operating temperature, thus losing the expected protection ability

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