LA1787M Datasheet, PDF (34/54 Pages) Sanyo Semicon Device – Single-Chip Tuner IC for Car Radios

LA1787M
FM Soft Muting (2)
Fig.21
R47 = 7.5 kΩ
DET out
10 kΩ
15 kΩ
200 kΩ
20 kΩ
Noise
FM Soft Muting (3)
R47 = 7.5 kΩ
Fig.22
DET out
10 kΩ
15 kΩ
30 kΩ
2 0kΩ
Noise
Antenna input — dBµ
VCC
200 kΩ
R
+
–
N-AGC
R
+
–
R
Antenna input — dBµ
Quadrature detector
Mute amp.
(VCA)
Mute
drive
Limiter
58
33
To MIX out
Open
200 kΩ
30 kΩ
Fig. 23
• FM muting off function
Forcing this pin to the ground level turns muting off.
Detector
output ⁰
1
20
When the pin is at the ground level, the noise convergence will
be 10 dB and the –3 dB limiting sensitivity will be about 0 dBµ.
Fig. 24
Antenna input
A12082
31
DET out
A11767
No. 6655-34/54