ELECTRICAL CHARACTERISTICS (continued.)

Symbol

Parameter

Test Condition

Min.

Typ.

Max.

Unit

BUS INPUT

Input Low Voltage

1V

Input High Voltage

3

V

Input Current

-5

5

µA

Output Voltage SDA

Acknowledge

0.4

0.8

V

0/30dB

2dB STEP

MUXOUTL

VOLUME

VOLUME

MUXOUTR

SPKR ATT

LEFT

LOUT

SCL

SDA

DIG_GND

ROUT

D98AU870

I

100K

100K

G

L-IN1

L-IN2

100K

100K

R-IN1

R-IN2

G

INPUT MULTIPLEXER

+ GAIN

SPKR ATT

RIGHT

SUPPLY

CREF

AGND

5

8

9

7

6

19

20

18

4

2

3

11

1

10

V

REF

0.47

µF

0.47

µF

0.47

µF

0.47

µF

10

µF

TEST CIRCUIT

APPLICATION SUGGESTIONS

The first and the last stages are volume control

blocks. The control range is 0 to -47dB (mute) for

the first one, 0 to -79dB (mute) for the last one.

Both of them have 1dB step resolution.

The very high resolution allows the implementation

of systems free from any noisy acoustical effect.

The TDA7449L audioprocessor provides 2 bands

tones control.

CREF

The suggested 10

µF reference capacitor (CREF)

value can be reduced to 4.7

µF if the application

requires faster power ON.

TDA7449L

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