TDA7541B Datasheet, PDF (41/77 Pages) STMicroelectronics – AM/FM car radio tuner IC with stereo decoder and intelligent selectivity system

TDA7541B
Functional description
Write operation
Following a START condition the master sends a slave address word with the R/W bit set to
"0". The device will generate an "acknowledge" after this first transmission and will wait for a
second word (the word address field). This 8-bit address field provides an access to any of
the 32 internal addresses. Upon receipt of the word address the TDA7541B slave device will
respond with an "acknowledge". At this time, all the following words transmitted to the
TDA7541B will be considered as Data. The internal address will be automatically
incremented. After each word receipt the TDA7541B will answer with an "acknowledge".
Read operation
If the master sends a slave address word with the R/W bit set to "1", the TDA7541B will
transmit one 8-bit data word. This data word includes the following informations.
bit0 (ISS filter, 1 = ON, 0 = OFF)
bit1 (ISS filter bandwidth, 1 = 80 kHz, 0 = 120 kHz)
bit2 (STEREO, 1 = STEREO, 0 = MONO)
bit3 (1 = PLL is locked in, 0 = PLL is locked out).
bit4 (fieldstrength indicator, 1 = lower as softmute threshold,
0 = higher as softmute threshold)
bit5 (adjacent channel indicator, 1 = adjacent channel present,
0 = no adjacent channel)
bit6 (deviation indicator, 1 = strong overdeviation present,
0 = no strong overdeviation)
bit7 (deviation indicator, 1 = overdeviation present,
0 = no overdeviation)
Doc ID 16048 Rev 1
41/77