High-temperature protection circuit structure of audio power amplifier circuit

Abstract

The invention relates to a high-temperature protection circuit structure of an audio power amplifier circuit. The high-temperature protection circuit structure comprises a temperature detection module and a gain adjustment module, wherein the temperature detection module outputs a corresponding gain adjustment signal along with the change of temperature, and the gain adjustment module is used for performing gain adjustment according to the gain adjustment signal output by the temperature detection module. By adopting the high-temperature protection circuit structure of the audio power amplifier circuit disclosed by the invention, the gain of the power amplifier at different temperatures is changed by monitoring the temperature, so that the problems of switch switching, circuit loss and sound interruption of the power amplifier caused by temperature change due to continuous temperature rise can be effectively avoided; aand according to the circuit structure, the temperature is monitored in real time, the over-temperature signal is continuously processed, and the gain of the power amplifier is changed, so that the distortion degree of the input audio signal is not changed, and the auditory experience is improved.

Description

technical field [0001] The invention relates to the technical field of circuit structures, in particular to the field of high-temperature processing of circuits, in particular to a high-temperature protection circuit structure of an audio power amplifier circuit. Background technique [0002] At present, power amplifier products have been popularized in life, and there are various products on the market that directly turn off the power amplifier after the temperature of the circuit rises, or control it by changing the audio signal; when these products work, they work with the power amplifier circuit. Prolonging the time or increasing the temperature of the working environment will cause the internal temperature of the circuit to rise and trigger the temperature protection. The temperature protection includes the following two processing methods: [0003] The first is to directly turn off the power amplifier and stop working until the temperature recovers, and the power ampli...

AI Technical Summary

Problems solved by technology

[0003] The first is to directly turn off the power amplifier and stop working until the temperature recovers, and the power amplifier resumes working; this operation method will cause the sound to be repeated intermittently, and the listening experience is not good;

[0004] The second is that the temperature protection triggers the protection signal. By lowering the audio signal amplitude, the power amplifier continues to work, but it will lead to increased distortion.

[0008] 3) The method of changing the gain by connecting the temperature-sensitive resistor in parallel to the feedback resistor: the resistance of the temperature-sensitive resistor changes greatly with the temperature change, and the parallel connection to the feedback resistor causes the feedback resistor to change greatly with temperature. Although the gain at high temperature can be improved, the gain The change is also relatively large, and the sound volume changes relatively large in the sense of hearing. The gain value of this method depends on the temperature control resistor, which is not easy to control;

[0009] 4) By adding the temperature detection module method on the heat sink: the temperature detected by this method is fed back to the chip to control the gain of the chip. Since there is a certain error between the heat sink and the actual internal temperature of the chip, the actual temperature of the heat sink is detected It may be lower than the chip temperature, resulting in detection errors and possibly burning out the circuit

The method of external heat sink temperature detection module, the integration of the circuit is not high, which increases the cost of customers

Images