TDA7404

I2C bus interface

25/35

Note 1: The attenuation is specified at high frequencies. Around the center frequency the value is different

depending on the programmed attenuation (see Section 4.4: Loudness).

Note 2: It is not recommended to use a gain more than 20 dB for system performance reason. In general, the

max. gain should be limited by software to the maximum value, which is needed for the system.

Table 9.

Loudness

MSB

LSB

Function

0

0

:

1

1

0

0

:

1

1

0

0

:

1

1

0

1

:

0

1

Attenuation

0 dB

-1 dB

:

-14 dB

-15 dB

0

0

0

1

1

0

1

0

1

Filter / Center Frequency

off (flat) 'D6 must be = 0'

400 Hz

800 Hz

2.4 kHz

0

1

Shape

Low boost

Low and high boost

0

1

Soft-step-Volume

off

on

Table 10.

Volume

MSB

LSB

Function

0

0

0

0

0

0

0

0

1

1

1

0

0

0

0

0

1

1

1

1

1

1

0

0

0

0

1

0

0

0

0

0

1

0

0

0

0

1

0

0

0

1

1

X

0

0

0

0

1

0

0

0

1

1

X

0

0

1

1

1

0

0

1

1

1

X

0

1

0

1

1

0

1

0

1

0

1

X

Gain/attenuation

not allow

not allow

+30.0 dB

+29.0 dB

:

+1.0 dB

0.0 dB

- 1.0 dB

- 2.0 dB

:

-78.0 dB

-79.0 dB

Mute

0

1

Diffin - mode

Single ended stereo

Differential Stereo