LA1845N Datasheet, PDF (4/10 Pages) Sanyo Semicon Device – Single-Chip Home Stereo IC

Pin Functions
Pin No.
Pin function
Pin voltage
LA1845N, 1845NM
Notes
1
FM IF input
Vreg
Input impedance r_i = 330 Ω
2
AM mixer output
V_CC
Connect the mixer coil between this pin and V_CC
3
REG
2.3
Vreg = 2.3 V
Equivalent circuit
1
3
2
A10635
A10636
3
A10635
4
AM IF input
Vreg
5
GND
0V
6
TU-LED
V_CC
7
ST-LED / AF-IF
V_CC
output
Input impedance r_i = 2 kΩ
Active low
Open collector
4
6
A10637
7
A10638
8
FM detector
V_CC
The 600BEAS-10471 (Toko Mfg. Co., Ltd.) is
recommended for detector coil.
9
V_CC
AM / FM IF
counter output,
10
output control
0V
switch, mute
switch
Phase comparator
11
low-pass filter
V_CC – 1.0
(AM/FM switching)
V10 ≤ 0.5 V: Reception state
1.4 V ≤ V10 ≤ 2.2 V: Muting on
V10 ≥ 3.5 V: IF counter output and muting on
The device operates in AM mode when a current
of over 200 µA flows from pin.12.
Limit values for the resistor:
2.7 kΩ (When V_CC = 7 V)
3.9 kΩ (8 V)
10
A10643
11
A10641
Continued on next page.
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