TDA7421N Datasheet, PDF (4/38 Pages) STMicroelectronics – AM/FM TUNER FOR CAR RADIO AND HI-FI APPLICATIONS

TDA7421N
PIN DESCRIPTION (Continued)
N.
Name
Function
20
LP IN3
FM-HS loop filter connection to op-amp inverting input
21
PLL VREF
Voltage reference to Op Amp noninverting input
22
PLL GND
PLL ground
23
SLEEP
I²C bus disconnect signal
24
SDA
I²C bus data
25
SCL
I²C bus clock
26
DIG VDD
Digital positive supply
27
DIG GND
Digital ground
28 (*)
IFC SSTOP
IF-Counter stop signal or
AM STEREO OUT AM IF2 amplifier output
29
CLN GND
“Clean” ground
30
IF2 GND
IF2 ground
31
AM AGC2 TC
AM 2^nd AGC time constant
32
AM DET
AM detector capacitor
33
AM BPF
AM IF filter
34
AM REF
Reference voltage of AM IF amplifier
35
AM IF2 in
AM IF2 amplifier input
36
IF2 VCC
IF2 positive supply
37
FM QUAD -
FM quadrature detector tank (differential -)
38
FM QUAD +
FM quadrature detector tank (differential +)
39
AUDIO OUT
FM MPX/AM Audio output
40 (*)
FM SD
AM SD
FM station detector output or
AM station detector output
41 (*)
FM SMETER
AM SMETER
FM DET ADJ
FM S-meter output or
AM S-meter output or
FM detector adjustment output
42
FM MUTE DRIVE FM mute time constant
43
FM BW TC
FM detuning detector time constant
44
IF1 GND
IF1 ground
45
FM LIM IN -
FM limiter negative input (differential -)
46
FM LIM IN +
FM limiter negative input (differential +)
47
IF1 VCC
IF1 positive supply
48
FM IF AMP2 OUT _{FM 2}^nd _{IF amplifier output}
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