LV47004P

No.A1798-4/11

External Components

Part Name

Recommended Value

Purpose

Remarks

C1 to C5

0.47

μF

Cuts DC voltage

The larger the constant value, the lower the cut-off frequency

The values of C1 to C5 must be the same

C6

22

μF

Reduces ripples

Reduces pop noise

The larger the constant value, the longer the amplifier ON/OFF time

C7

2200

μF

Ripple filter

Eliminating power supply ripples

C8

0.1

μF

Improves oscillation stability

Reducing high-frequency noise

C9

1

μF

Reduces pop noise

The larger the constant value, the longer the mute ON/OFF time

R1

10k

Ω

Reduces pop noise

The larger the constant value, the longer the mute ON/OFF time

R2

4.7k

Ω

Pull-up resistor

* The components and constant values within the test circuit are used for confirmation of characteristics and are not guarantees that incorrect or trouble will not

occur in application equipment.

Description of Operation

1. Standby switch function (pin 4)

Threshold voltage of the pin 4 is set by about 2VBE.

The amplifier is turned on by the applied voltage of 2.5V or more. Also, the amplifier is turned off by the applied

voltage of 0.5V or less.

Fig1 Standby equivalent circuit

2. Muting function (pin 22)

The muted state is obtained by setting pin 22 to the ground potential, enabling audio muting.

The muting function is turned on by the applied voltage of 1V or less to the resistance of 22pin (Mute pin). And the

muting function is turn off tjis pin opens.

Also, the time constant of the muting function is determined by external capacitor and resistor constants.

It is concerned with a pop noise in amplifier ON/OFF and mute ON/OFF. After enough examination, please set it.

Fig2 Mute equivalent circuit

4

STBY

10k

Ω

30k

Ω

+

MUTE

MUTE

OFF

ON

10k

Ω

18k

Ω

1

μF

about

50

μA

about

2.5V

200

Ω

22