Typical Application

Truth Table for Logic Inputs (Note 16)

Headphone

Sense

Gain Select

Mode

Mute

Output Stage Set

To

Volume Control

X

0

0

0

Internal Gain

On

X

0

0

0

Internal Gain

On

X

1

0

0

External Gain

On

X

1

0

0

External Gain

On

On

0

1

0

Internal Gain

On

Off

0

1

0

External Gain

On

On

1

1

0

External Gain

On

Off

1

1

0

Internal Gain

On

X

X

X

1

X

Muted

Note 16: If system beep is detected on the Beep In pin (pin 11), the system beep will be passed through the bridged amplifier regardless of the logic of the Mute

and HP sense pins.

20028003

FIGURE 2. Typical Application Circuit ( MT / MH Package Pinout )

www.national.com

5