TDA7786 datasheet(24/54 Pages) STMICROELECTRONICS

24 / 54 page

Function description

TDA7786, TDA7786M

24/54

DocID026122 Rev 5

The "read" sequence is similar to the "write" and it has the same constraints for start, stop,

data-latching and the following differences:



the chip address must always be sent by the microprocessor to the TDA7786x; the

address must be 0xC3 (if C2 had been selected at boot) or 0xC9 (if 0xC8 had been

selected at boot);



the header is transmitted after the chip address (the same happens for "write") before

data are transferred from the TDA7786x to the microprocessor. See the relevant

technical documentation for details on the frame format;



when data are transmitted from the TDA7786x to the µP, the latter keeps the SDA line



the acknowledge pulse is generated by the µP for those data bytes that are sent by the

TDA7786x to the µP. Failure of the µP to generate an ACK pulse on the 9th CLK pulse

has the same effect on the TDA7786x as a STOP.

The maximum clock speed is 500 kbit/s.

Warning:

When the TDA7786x is not powered on, the internal ESD

protection diodes act as a pull-down keeping the I2C lines

voltage below 2 V. This implies that the I2C bus connected to

the TDA7786x may not be used to drive other devices when

the TDA7786x is powered off.

TDA7786 数据表(PDF) 24 Page - STMicroelectronics