LA1781M_09 Datasheet, PDF (17/48 Pages) Sanyo Semicon Device – For Car Radios Single-Chip Tuner IC

Continued from preceding page.
Pin No.
Pin function
6
Front end VCC AM/FM
switching
62
1st MIX
INPUT
LA1781M
Pin description
Pin 6 functions both as the FM front
end VCC and the AM/FM switching
circuit.
V6 voltage
Mode
When 8V → FM
OPEN → AM
First mixer input
The input impedance is about 10kΩ.
Equivalent circuit
SD
+
8V
VCC 510Ω
6
FM.F.E
AGC ^100kΩ
3
GND
AM/FM
switching circuit
3.3V
to RF
Amp.
62
AM 1st
MIX
10kΩ
2.1V
10
AM 2nd OSC
Crystal oscillator circuit
The Kinseki, Ltd. HC-49/U-S and
a CL of 20pF must be used.
10kΩ
5.6V
20pF
33pF
10
X tal
to 2nd
MIX
No.6038-17/48