LA42205

No.A0714-4/7

External Components

C1, C2

: Input coupling capacitors. A value of 47

μF is recommended.

The input pin potential is 0.7V.

C3

: Capacitor which sets the starting time of the ripple filter and amplifier. A value of 100

μF is recommended.

C4, R1

: Capacitor and resistor for muting function. C4 is necessary even when the mute function is not used.

C5

: This capacitor increases the oscillator margin. We recommend a value of 0.1

μF.

C6

: Power supply capacitor.

1. Muting function (pin 7)

The muting function is turned on when the pin 7 voltage is 1.5V (minimum) or higher.

The VM applied voltage is set so that the pin 7 voltage will be 1.5V or higher.

The muting time constant is determined by an C4, R1 circuit, and the component values must be determined by a

careful analysis, since they are related to impulse noise that occurs when the muting function is turned on or off. Also

note that since C4 affects the occurrence of impulse noise when the amplifier is turned on or off, it will be required if

the muting function is not used.

2. Standby function (pin 6)

The amplifier is turned on by applying a level of 2.5V (minimum) or higher to pin 6.

Pin 6 control voltage

Pin 6 voltage

Amplifier

Standby

0 to 0.5

Off

On

2.5 to VCC

On

Off

The limit resistor RSTB may be inserted if the VSTB applied voltage is comparatively high and there is a need to

suppress the pin 6 sink current.

Mute

Standby

+

7

C4

10

μF

/6.3V

R1

15k

Ω

7.5k

Ω

2k

Ω

1k

Ω

VCC

VM

20k

Ω

6

RSTB

1.5k

Ω

15k

Ω

VCC

2VBE

VS

30k

Ω