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, comprising a temperature detection module and a gain adjustment module, the temperature detection module outputs a corresponding gain adjustment signal as the temperature changes, and the gain adjustment module is used to output the gain according to the temperature detection module Adjust the signal for gain adjustment. The high-temperature protection circuit structure of the audio power amplifier circuit of the present invention is adopted. By monitoring the temperature and changing the gain of the power amplifier at different temperatures, it can effectively avoid the switch switching caused by the continuous rise of the temperature and the temperature change, resulting in circuit loss and temperature. Protect and shut down the sound of the power amplifier; the circuit structure monitors the temperature in real time, continuously processes the signal when the temperature is over, and changes the gain of the power amplifier, so that the distortion of the input audio signal does not change, which improves the listening experience .

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, and 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 also various products on the market that directly turn off the power amplifier after the circuit temperature rises, or control the audio signal by changing the audio signal; when such products work, with the power amplifier circuit working If the time is prolonged or the temperature of the working environment increases, the internal temperature of the circuit will 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 not work until the temperature recovers and the power am...

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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

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