LA1787M Datasheet, PDF (15/54 Pages) Sanyo Semicon Device – Single-Chip Tuner IC for Car Radios

Continued from preceding page.
Pin No.
Function
44
IF AGC
45
IF output
LA1787M
Description
G1; Used for time constant
switching during seeks.
• Reception
τ = 2.2 µF × 300 kΩ
• Seek
τ = 2.2 µF × 10 Ω
The external capacitors are
connected to V_CC.
This is because the IF amplifier
operates referenced to V_CC.
Equivalent circuit
0.022µF
+
240kΩ
VCC
C
2.2µF
42
44
VCC
DET
50kΩ
G1
SEEK
ON
10Ω
50kΩ
IF
AGC
Pin 40 VCC
A13583
The IF amplifier load
45
Pin 40 VCC
AM antenna damping
46
drive output
Wide band AGC input
I46 = 6 mA (maximum)
This is the antenna damping
current.
DET
VCC
50pF
46
100Ω
A13584
20kΩ
VCC
W.AGC AMP.
ANT DAMPING
DRIVER
A13585
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