Comparator and D-class audio power amplifier comprising comparator

Abstract

The invention discloses a comparator and a D-class audio power amplifier comprising the comparator; the comparator comprises an input circuit used for receiving a differential signal and generating an amplified output signal, a delay adjusting circuit used for setting a delay window and adjusting the output signal of the input circuit, and an output circuit used for receiving the output signal of the input circuit and generating an output signal with wide amplitude. The comparator and the D-class audio power amplifier provide the comparator which can work normally in a wide voltage range from a power voltage to a ground voltage; with the adjustment of the delay adjusting circuit, the delay window can be set precisely, thereby suppressing noise well; and the output circuit can response quickly and is characterized by large output swing amplitude.

Description

technical field [0001] The invention mainly relates to the field of analog integrated circuits, in particular to a wide common-mode input hysteresis voltage comparator and a class D audio power amplifier including the comparator. Background technique [0002] Traditional Class A, Class B or Class AB audio amplifiers directly amplify analog signals, and the amplifier must work in the linear amplification region. Although the class AB audio amplifier has high fidelity, it consumes a lot of power and the conversion efficiency is less than 50%, which no longer meets the needs of green energy saving. Compared with it, the Class D amplifier has a huge advantage. Its characteristic of working in the switch state makes its theoretical efficiency reach 100%, and it is also more than 80% in the actual situation, thus greatly reducing the power consumption and at the same time The area occupied by chips and PCB (Printed Circuit Board, printed circuit board) is reduced, and it has broa...

AI Technical Summary

Problems solved by technology

[0008] For normal operation of the above comparators, the common-mode input is limited to V SS +V DS +V GS CM DD or V SS CM DD -|V DS |-|V GS |, does not meet the requirements of PWM comparator wide common mode input

At the same time, the output swing and noise are also the main reasons for limiting its use as a PWM comparator, so the above-mentioned comparator cannot meet the requirements of a PWM comparator in a class D audio power amplifier.

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