la7567b Sanyo Semiconductor Corporation, la7567b Datasheet - Page 12

• Manufacturer Part Number: la7567b
• Description: Tv And Vcr Vif/sif If Signal-processing Circuit With Pal/ntsc Multi-format Audio Support
• Manufacturer: Sanyo Semiconductor Corporation

Continued from preceding page.
Pin No.
16
17
18
19
20
1st SIF AGC FILTER
IF AGC FILTER
VIF input
GND
Pin
• First SIF AGC filter connection.
• When used in an intercarrier system:
• IF AGC filter connection
• VIF amplifier input.
This IC adopts an average value AGC technique. The first
SIF conversion gain is about 30 dB, and the AGC range is
over 50 dB. A 0.01 µF capacitor is normally used in filter
connected to this pin.
Connect this pin (pin 16) to ground. The IC internal switch
will operate to connect the intercarrier output to the SIF
converter input.
The signal peak-detected by the built-in AGC detector is
converted to the AGC voltage at pin 17. Additionally, a
second AGC filter (a lag-lead filter) used to create the dual
time constants is provided internally in the IC.
Use a 0.022-µF capacitor as the external capacitor, and
adjust the value according to the sag, AGC speed, and
other characteristics.
The input circuit is a balanced circuit, and the input circuit
constants are:
R
C
1.5 kΩ
3 pF
Description
LA7567B, 7567BM
18
19
1 k
Equivalent circuit
17
16
1 k
1 k
Continued on next page.
INTER/SPLIT SW
LO=INTER
No. 6099-12/15
A12042
A12041
A12040