U4459B
IF Amplifier for Cable DVB Processing
Description
The U4459B is an integrated bipolar circuit suitable for
the IF processing in cable-DVB receiver (DVB =
Digital
Video Broadcasting)
and cable network application.
The circuit contains a wideband IF amplifier, mixer stage,
gain control for the IF amplifier and a tuner-AGC
(Automatic
Gain Control)
with adjustable take over point
for an additional external preamplifier (tuner).
Features
D
Input frequency range 30 to 50 MHz (1st IF)
D
Wideband IF amplifier with high linearity
D
Gain control of the IF amplifier by external
dc voltage
D
High output level of mixed signal (2nd IF)
(up to 2.4 V, peak-to-peak value)
D
Tuner-AGC with adjustable take over point for a
preamplifier
D
Supply voltage range 6.8 to 13.5 V
Package:
DIP16
D
Mixer stage with local oscillator input
(symmetrical or unsymmetrical)
LO in
8
IF1 in
1
IF amp
LO in
9
95 9636
6
16
IF1 in
Mixer
IF2 out
IF gain
control
3
I
Tun
Bandgap
14
V
S
2
V
Tun
5
V
Gain
13
BG
4,15
GND
Figure 1. Block diagram
TELEFUNKEN Semiconductors
Rev. A1, 15-Jul-96
1 (7)
TEMIC [ TEMIC SEMICONDUCTORS ]
