TPA0212

STEREO 2-W AUDIO POWER AMPLIFIER

WITH FOUR SELECTABLE GAIN SETTINGS AND MUX CONTROL

SLOS284 – NOVEMBER 1999

31

POST OFFICE BOX 655303

APPLICATION INFORMATION

PC BEEP operation

The PC BEEP input allows a system beep to be sent directly from a computer through the amplifier to the

speakers with few external components. The input is activated automatically. When the PC BEEP input is active,

both of the LINEIN and HPIN inputs are deselected and both the left and right channels are driven in BTL mode

with the signal from PC BEEP. The gain from the PC BEEP input to the speakers is fixed at 0.3 V/V and is

independent of the volume setting. When the PC BEEP input is deselected, the amplifier will return to the

previous operating mode and volume setting. Furthermore, if the amplifier is in shutdown mode, activating PC

BEEP will take the device out of shutdown and output the PC BEEP signal, then return the amplifier to shutdown

mode.

minimum of 8 rising edges. When the signal is no longer detected, the amplifier will return to its previous

operating mode and volume setting.

If it is desired to ac-couple the PC BEEP input, the value of the coupling capacitor should be chosen to satisfy

equation 14:

C

PCB w

1

2

p

ƒ

PCB

(100 k

W)

(14)

The PC BEEP input can also be dc-coupled to avoid using this coupling capacitor. The pin normally sits at midrail

when no signal is present.

shutdown modes

minimum level during periods of nonuse for battery-power conservation. The SHUTDOWN input terminal

should be held high during normal operation when the amplifier is in use. Pulling SHUTDOWN low causes the

unconnected because amplifier operation would be unpredictable.

Table 6. HP/LINE, SE/BTL, and Shutdown Functions

INPUTS†

AMPLIFIER STATE

HP/LINE

SE/BTL

SHUTDOWN

INPUT

OUTPUT

X

X

Low

X

Mute

Low

Low

High

Line

BTL

Low

High

High

Line

SE

High

Low

High

HP

BTL

High

High

High

HP

SE

† Inputs should never be left unconnected.

X = do not care