TDA7405_04 STMICROELECTRONICS [STMicroelectronics], TDA7405_04 Datasheet - Page 39

• Manufacturer Part Number: TDA7405_04
• Description: EQUALIZER CARRADIO SIGNAL PROCESSOR
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

12 I²C BUS INTERFACE
12.1 Interface Protocol
The interface protocol comprises:
-a start condition (S)
-a chip address byte (the LSB bit determines read / write transmission)
-a subaddress byte
-a sequence of data (N-bytes + acknowledge)
-a stop condition (P)
S = Start
R/W ="0" -> Receive-Mode (Chip could be programmed by µP)
ACK = Acknowledge
P = Stop
MAX CLOCK SPEED 500kbits/s
12.1.1Auto increment
If bit I in the subaddress byte is set to "1", the autoincrement of the subaddress is enabled.
12.1.2TRANSMITTED DATA (send mode)
SM = Soft mute activated
ST = Stereo
P = Pause
X = Not Used
The transmitted data is automatically updated after each ACK. Transmission can be repeated without new chi-
paddress.
12.1.3Reset Condition
A Power-On-Reset is invoked if the Supply-Voltage is below than 3.5V. After that the following data is written
automatically into the registers of all subaddresses :
The programming after POR is marked bold-face / underlined in the programming tables.
With this programming all the outputs are muted to V
S 1 0 0 0 1 1 0 R/W ACK C AZ
MSB
MSB
X
1
MSB
"1" -> Transmission-Mode (Data could be received by µP)
CHIP ADDRESS
X
1
X
1
X
1
LSB
X
1
P
1
MSB
ST
1
SUBADDRESS
I
LSB
LSB
SM
A
0
A
REF
A
(V
OUT
A
LSB
= V
A ACK
DD
/2).
MSB
DATA 1 ... DATA n
DATA
LSB
TDA7405
ACK
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P