External Components Description

Components

Functional Description

1.

C

IN

This is the input coupling capacitor. It blocks the DC voltage and couples the input signal to the

amplifier’s input terminals. C

Impedance) at f

πR

2.

C

S

This is the supply bypass capacitor. It filters the supply voltage applied to the V

reduce the noise at the V

3.

C

B

This is the BYPASS pin capacitor. It filters the V

PSRR.

4.

C

OUT

This is the output coupling capacitor. It blocks the DC voltage and couples the output signal to the

speaker load R

πR

5.

R

3D

This resistor sets the gain of the National 3D effect. Please refer to the National 3D Enhancement

section for information on selecting the value of R

6.

C

3D

This capacitor sets the frequency at which the National 3D effect starts to occur. Please refer to the

National 3D Enhancement section for information on selecting the value of C

Typical Performance Characteristics (Note 11)

LM4857SP THD+N vs Frequency

LM4857SP THD+N vs Frequency

20079755

V

R

Ω; Mode 7; 0dB Gain

20079756

V

R

Ω; Mode 7; 0dB Gain

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