Philips Semiconductors
Product specification
Hi-fi stereo audio processor; I2C-bus
TDA8425
Subaddress
After the module address byte a second byte is used to select the following functions:
• Volume left, volume right, bass, treble and switch functions
The subaddress SAD is stored within the TDA8425. Table 1 defines the coding of the second byte after the module
address MAD.
Table 1 Second byte after module address MAD
128
MSB
7
64
32
5
16
4
8
3
4
2
2
1
1
0
LSB
function
6
volume left
volume right
bass
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
1
1
0
0
1
0
1
0
treble
switch functions
subaddress SAD
The automatic increment feature of the slave address enables a quick slave receiver initialization, within one
transmission, by the I2C-bus controller (see Fig.5).
Definition of 3rd byte
A third byte is used to transmit data to the TDA8425. Table 2 defines the coding of the third byte after module address
MAD and subaddress SAD.
Table 2 Third byte after module address MAD and subaddress SAD
MSB
7
LSB
0
function
6
5
4
3
2
1
volume left
volume right
bass
VL
VR
BA
TR
S1
1
1
1
1
1
1
1
1
1
1
V05
V15
1
V04
V14
1
V03
V13
BA3
TR3
STL
V02
V12
BA2
TR2
ML1
V01
V11
BA1
TR1
ML0
V00
V10
BA0
TR0
IS
treble
1
1
switch functions
MU
EFL
October 1988
6
NXP [ NXP ]
