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TDA7409
2.0 I
2
C BUS INTERFACE
2.1 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)
■ the max. CLOCK SPEED is 500kbits/s
S = Start
R/W ="0" -> Receive-Mode (Chip could be programmed by P)
"1" -> Transmission-Mode (Data could be received by P)
ACK = Acknowledge
P = Stop
2.2 TRANSMITTED DATA (send mode)
SM = Soft mute activated
X = Not Used
The transmitted data is automatic updated after each ACK. Transmission can be repeated without new chipaddress.
2.3 Reset 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
REF
(V
OUT
= V
DD
/2).
Note : All the blank bits in the following tables are "don't care"-bits.
MSB LSB
XXXXXXXSM
MSB LSB
11111110
S1000100R/W ACK ACK ACK ACK P
MSB
LSB MSB LSB MSB LSB
CHIP ADDRESS
D99AU1044
I
3
I
0
SUBADDRESS DATA 1 to DATA n
I
2
I
1
A
3
A
2
A
1
A
0
Obsolete Product(s) - Obsolete Product(s)
