TDA7461NDTR STMicroelectronics, TDA7461NDTR Datasheet - Page 15

• Manufacturer Part Number: TDA7461NDTR
• Description: IC PROCESSOR CAR RAD SGNL SO-28
• Manufacturer: STMicroelectronics
• Type: Car Signal Processorr

Specifications of TDA7461NDTR

• Applications: Automotive Systems
• Mounting Type: Surface Mount
• Package / Case: 28-SOIC (7.5mm Width)
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

TDA7461
3.1.3
3.2
The TDA7461 can be configured with an additional input; if the AC coupling before the
speaker stage is not used (bit 7 in subaddress 5 set to "1") ACINL and ACINR pins can be
used as an additional stereo input.
Figure 4.
AutoZero
In order to reduce the number of pins there is no AC coupling between the In-Gain and the
following stage, so that any offset generated by or before the In-Gain stage would be
transferred or even amplified to the output. To avoid that effect a special offset cancellation
stage called AutoZero is implemented.
To avoid audible clicks the audioprocessor is muted before the loudness stage during this
time. In some cases, for example if the μP is executing a refresh cycle of the I
programming, it is not useful to start a new AutoZero action because no new source is
selected and an undesired mute would appear at the outputs. For such applications the
TDA7461 could be switched in the "Auto Zero Remain" mode (Bit 6 of the subaddress byte).
If this bit is set to high, the DATABYTE 0 could be loaded without invoking the AutoZero and
the old adjustment value remains.
Mux output
The MUX_L and MUX_R outputs can provide selectively the output of the input multiplexer
(Speaker RF register, Byte 8, bit 6=1) or the output of the stereo decoder (Speaker RF
register Byte 8 bit 6=0).
If bit D3 byte 10 (Stdec Register) is set to 1, then the stdec signal is automatically muted,
when another source is selected at the input multiplexer.
CASSETTE
PH_GND
CDGND
PHONE
MPX
AM
CD
Input stages
100K
100K
100K
100K
STEREODECODER
15K
15K
15K
15K
+
+
-
15K
-
15K
15K
15K
Description of the audio processor part
D97AU633A
2
IN GAIN
C bus
15/48