EL4095C
Video Gain Control Fader Multiplexer
Applications Information
The EL4095 is a general-purpose two-channel
fader whose input channels each act as a current-
feedback amplifier (CFA) input Each input can
have its own gain factor as established by exter-
nal resistors For instance the Test Circuit shows
two channels each arranged as
a
1 gain with the
traditional single feedback resistor R
F
connected
from V
OUT
to the
b
V
IN
of each channel
The EL4095 can be connected as an inverting
amplifier in the same manner as any CFA
Frequency Response
Like other CFA’s there is a recommended feed-
back resistor which for this circuit is 1 KX The
value of RF sets the closed-loop
b
3 dB band-
width and has only a small range of practical
variation The user should consult the typical
performance curves to find the optional value of
R
F
for a given circuit gain In general the band-
width will decrease slightly as closed-loop gain is
increased R
F
can be reduced to make up for
bandwidth loss Too small a value of R
F
will
cause frequency response peaking and ringing
during transients On the other hand increasing
R
F
will reduce bandwidth but improve stability
EL4095C In Inverting Connection
4095 – 27
11
ELANTEC [ ELANTEC SEMICONDUCTOR ]
