Note 16: All bumps have the same thermal resistance and contribute equally when used to lower thermal resistance. The LM4838ITL demo board (views featured

The planes measure 1,900mils x 1,750mils (48.26mm x 44.45mm) and aid in spreading heat due to power dissipation within the IC.

Typical Application

Truth Table for Logic Inputs (Note 17)

Gain

Sel

Mode

Headphone

Sense

Mute

Shutdown Output Stage Set To

DC Volume

Output Stage

Configuration

0

0

0

0

0

Internal Gain

Fixed

BTL

0

0

1

0

0

Internal Gain

Fixed

SE

0

1

0

0

0

Internal Gain

Adjustable

BTL

0

1

1

0

0

Internal Gain

Adjustable

SE

1

0

0

0

0

External Gain

Fixed

BTL

1

0

1

0

0

External Gain

Fixed

SE

1

1

0

0

0

External Gain

Adjustable

BTL

1

1

1

0

0

External Gain

Adjustable

SE

X

X

X

1

0

Muted

X

Muted

X

X

X

X

1

Shutdown

X

X

Note 17: If system beep is detected on the Beep In pin, the system beep will be passed through the bridged amplifier regardless of the logic of the Mute and HP

sense pins.

20013303

FIGURE 2. Typical Application Circuit ( LQ Package Pinout )

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