LA1787M Datasheet, PDF (6/54 Pages) Sanyo Semicon Device – Single-Chip Tuner IC for Car Radios

Pin Descriptions
Pin No.
Function
LA1787M
Description
1
Antenna damping drive
An antenna damping current flows
when the RF AGC voltage (pin 2)
reaches V_CC – V_D.
Equivalent circuit
ANT
VCC
62 pin
RF
AGC
1000pF
100Ω
1
1000pF
300Ω
100Ω
VCC
A13555
2
RF AGC
3
F.E.GND
4
OSC
7
AM OSC
Used to control the FET
second gate.
Oscillator connection
FET
2nd GATE
+
12kΩ
2
N
AGC
DET
KEYED
AGC
ANT
DAMPING
DRIVER
W
AGC
DET
VCC
A13556
VCC
4
25pF
VT
2kΩ
20pF
A13557
7
VCC
AM first oscillator
This circuit can oscillator up to the
SW band.
An ALC circuit is included.
ALC
A13558
Continued on next page.
No. 6655-6/54