EL2090C
EL2090C
100 MHz DC-Restored Video Amplifier
Features
Complete video level restoration
system
0 01% differential gain and 0 02
differential phase accuracy at
NTSC
100 MHz bandwidth
0 1 dB flatness to 20 MHz
Sample-and-hold has 15 nA
typical leakage and 1 5 pC charge
injection
System can acquire DC
correction level in 10
ms
or 5 scan
lines of 2
ms
each to IRE
V
S
e
g
5V to
g
15V
TTL CMOS hold signal
General Description
The EL2090C is the first complete DC-restored monolithic vid-
eo amplifier sub-system It contains a very high-quality video
amplifier and a nulling sample-and-hold amplifier specifically
designed to stabilize video performance When the HOLD logic
input is set to a logic 0 during a horizontal sync the sample-
and-hold amplifier may be used as a general-purpose op-amp to
null the DC offset of the video amplifier When the HOLD in-
put goes to a logic 1 the sample-and-hold stores the correction
voltage on the hold capacitor to maintain DC correction during
the subsequent scan line
The video amplifier is optimized for video characteristics and
performance at NTSC is nearly perfect It is a current-feedback
amplifier so that
b
3 dB bandwidth changes little at various
closed-loop gains The amplifier easily drives video signal levels
into 75X loads With 100 MHz bandwidth the EL2090 is also
useful in HDTV applications
The sample-and-hold is optimized for fast sync pulse response
The application circuit shown will restore the video DC level in
five scan lines even if the HOLD pulse is only 2
ms
long The
output impedance of the sample-and-hold is low and constant
over frequency and load current so that the performance of the
video amplifier is not compromised by connections to the DC
restore circuitry
The EL2090C is fabricated in Elantec’s proprietary Comple-
mentary Bipolar process which produces NPN and PNP tran-
sistors with equivalent AC and DC performance The EL2090C
is specified for operation over the 0 C to 75 C temperature
range
Applications
Input amplifier in video
equipment
Restoration amplifier in video
mixers
Ordering Information
Part No Temp Range
Pkg
Outline
EL2090CN 0 C to
a
75 C 14-Pin P-DIP MDP0031
EL2090CM 0 C to
a
75 C 16-Lead SOL MDP0027
Connection Diagrams
14-Pin DIP Package
16-Pin SOL Package
January 1996 Rev D
2090 – 1
2090 – 2
Note
All information contained in this data sheet has been carefully checked and is believed to be accurate as of the date of publication however this data sheet cannot be a ‘‘controlled document’’ Current revisions if any to these
specifications are maintained at the factory and are available upon your request We recommend checking the revision level before finalization of your design documentation Patent pending
CMS 2090DS
1990 Elantec Inc
ELANTEC [ ELANTEC SEMICONDUCTOR ]
