EL4094CN ELANTEC [Elantec Semiconductor], EL4094CN Datasheet - Page 10

• Manufacturer Part Number: EL4094CN
• Description: Video Gain Control/Fader
• Manufacturer: ELANTEC [Elantec Semiconductor]

Applications Information
The differential gain error is kept to 0 3% and
the differential phase to 0 15 or better over the
entire input range
The EL4094 as an Adjustable Filter
Equalizers are used to adjust the delay or fre-
quency response of systems A typical use is to
compensate for the high-frequency loss of a cable
system ahead of the cable so as to create a flat
response at the far end A generalized scheme
with the EL4094 is shown below
EL4094C
Video Gain Control Fader
a
6 dB to
General Adjustable Equalizer
b
Contd
6 dB Linearized Level Control
10
For an adjustable preemphasis filter for instance
filter A might be an all-pass filter to compensate
for the delay of filter B a peaking filter Fading
the gain from A to B provides a variable amount
of peaking but constant delay
The EL4094 as a Phase Modulator
To make a phase modulator filter A might be a
leading-phase network and filter B a lagging net-
work The wide bandwidth of the gain-control in-
put allows wideband phase modulation of the
carrier applied to the main input Of course the
carrier and gain inputs must not be digital but be
reasonably clean sinewaves for the modulation to
be accurate
4094 – 13
4094 – 15