u4460bg ETC-unknow, u4460bg Datasheet - Page 2

• Manufacturer Part Number: u4460bg
• Description: Video Amplifier With Fpll Demodulation
• Manufacturer: ETC-unknow

Pin description
Circuit description
Vision IF amplifier
The video IF signal (VIF) is fed through a SAW filter to
the VIF input (Pin 5–6). The VIF amplifier consists of
three AC–coupled amplifier stages. Each differential
amplifier is gain controlled by the automatic gain control
(VIF–AGC). Output signal of the VIF amplifier is applied
to the FPLL carrier generation and the video
demodulator.
VIF–AGC and adjustable tuner AGC
At Pin 7 the VIF–AGC charges/discharges the AGC
capacitor to generate a control voltage for setting gain of
VIF amplifier and tuner in order to keep the video output
signal at a constant level. Therefore the sync level of the
U4460BG
2 (9)
21, 22
5, 6
Pin
10
11
12
13
14
15
16
17
18
19
20
23
24
25
26
27
28
1
2
3
4
7
8
9
Symbol
V
C
R
V
GND
GND
GND
V
V
R
C
n.c.
n.c.
n.c.
n.c.
n.c.
I
n.c.
n.c.
n.c.
n.c.
n.c.
n.c.
n.c.
LF
comp
i,VIF
AGC
o,vid
AFC
V
tun
vco
top
ref
s
not connected
not connected
Ground
not connected
VIF input (symmetrical)
VIF–AGC (time constant)
Ground
not connected
not connected
Take over point, tuner AGC
Tuner AGC output current
Video output
not connected
not connected
not connected
Ground
Internal reference voltage
Loop filter
AFC switch
VCO circuit
AFC output
Supply voltage
not connected
not connected
Offset compensation
not connected
Function
Preliminary Information
demodulated video signal is the criterion for a fast charge/
discharge of the AGC capacitor.
The control voltage (AGC voltage at Pin 7) is transferred
to an internal control signal and fed to the tuner AGC to
generate the tuner AGC current at Pin 12 (open collector
output). Take over point of the tuner AGC can be adjusted
at Pin 11 by a potentiometer or an external DC voltage
(from interface circuit or microprocessor).
V
V
V
i
i
O
GND
C
, VIF
, VIF
GND
R
, vid
AGC
n.c.
n.c.
n.c.
n.c.
n.c.
n.c.
I
top
tun
10
11
13
12
14
Figure 2. Pin configuration
1
2
3
4
5
6
7
8
9
TELEFUNKEN Semiconductors
95 10650
Rev. A1: 15.08.1995
21
26
25
24
23
22
19
18
17
16
15
28
27
20
n.c.
R
n.c.
n.c.
V
V
V
V
n.c.
LF
C
GND
n.c.
n.c.
AFC
comp
S
VCO
Ref
VCO