EL4421C/22C/41C/42C/43C/44C
Multiplexed-Input Video Amplifiers
Typical Performance Curves Ð Contd.
Supply Current vs
Supply Voltage
Supply Current vs
Temperature
4421–31
4421–32
8-Pin Package
Power Dissipation vs
Ambient Temperature
14-Pin Package
Power Dissipation vs
Ambient Temperature
4421–33
4421–34
Applications Information
General Description
The EL44XX family of video mux-amps are com-
posed of two or four input stages whose inputs
are selected and control an output stage. One of
the inputs is active at a time and the circuit be-
haves as a traditional voltage-feedback op-amp
for that input, rejecting signals present at the un-
selected inputs. Selection is controlled by one or
two logic inputs.
EL4443 and EL4444, on the other hand, have all
b
that the input stage can be wired for independent
gains and gain polarities with separate feedback
networks.
a
inputs and inputs brought out separately so
The EL4421, EL4441, and EL4443 are compen-
sated for unity-gain stability, while the EL4422,
EL4442, and EL4444 are compensated for a fed-
a
back gain of 2, ideal for driving back-terminat-
ed cables or maintaining bandwidth at higher
fed-back gains.
The EL4421, EL4422, EL4441, and EL4442 have
b
all inputs wired in parallel, allowing a single
feedback network to set the gain of all inputs.
These devices are wired for positive gains. The
9
ELANTEC [ ELANTEC SEMICONDUCTOR ]
