LA1781M_09 Datasheet, PDF (24/48 Pages) Sanyo Semicon Device – For Car Radios Single-Chip Tuner IC

Notes on 3D AGC (Keyed AGC)
LA1781M
VCC
55
W-AGC
DET
58
N-AGC
DET
90μA
S-meter
+
--
VCC
+
--
1
ANT
DUMPING
2
39
24
+
VS-meter
Fig. 8
• The antenna damping current from the pin due to the pin diode flows when the V2 pin reaches the VCC - VBE level.
• The narrow AGC operates as follows.
When pin V39 > pin V24 : The narrow AGC turns off.
When pin V39 < pin V24 : The narrow AGC turns on.
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