Auxiliary audio power amplifier circuit design based on LM4730

　　Circuit principle: The picture shows the auxiliary audio power amplifier circuit of LM 4730 . The audio input signal passes through the potentiometers Rv, CIN, and RB and then is added to the input terminal 8 of the LM 4730. After amplification, it is output by pin 3 and sent to the speaker through L and R (the number in the parentheses is the B pin number of the internal amplifier). Rv is the volume potentiometer, used to adjust the volume; RIN is to set the DC bias working point of the amplifier, and forms an input high-pass filter with CIN; RSN and CSN are used to reduce the instability of the high-end frequency of the amplifier; L, R It provides high impedance for high frequencies and low impedance channel for audio to prevent high frequency self-excitation.