US Patent No. 10,193,506

METHODS AND CIRCUITS TO REDUCE POP NOISE IN AN AUDIO DEVICE


Patent No. 10,193,506
Issue Date January 29, 2019
Title Methods And Circuits To Reduce Pop Noise In An Audio Device
Inventorship Ru Feng Du, Shenzhen (CN)
Qi Yu Liu, Shenzhen (CN)
Assignee

Claim of US Patent No. 10,193,506

1. A circuit, comprising:a first amplifier having first and second inputs coupled to a first differential input stage biased by a first current source and having a first output;
a second amplifier having first and second inputs coupled to a second differential input stage biased by a second current source and having a second output,
wherein the first inputs of the first and second differential input stages are both coupled to receive a same reference voltage,
wherein the second input of the first amplifier is configured to receive an input signal, and
wherein the second input of the second amplifier is configured to receive an output signal; and
a bias control circuit comprising a third amplifier having first and second inputs coupled to a third differential input stage and biased by a third current source, said bias control circuit further having a first output configured to control the first current source and a second output configured to control the second current source.