®
EL4581
Data Sheet
August 16, 2002
FN7172
Sync Separator, 50% Slice, S-H, Filter
The EL4581 extracts timing informa-
tion from standard negative going
video sync found in NTSC, PAL, and
SECAM broadcast systems. It can also be used in non stan-
dard formats and with computer graphics systems at higher
scan rates, by adjusting a single external resistor. When the
input does not have correct serration pulses in the vertical
interval, a default vertical output is produced.
Outputs are composite sync, vertical sync, burst/back porch
output, and odd/even output. The later operates only in inter-
laced scan formats.
The EL4581 provides a reliable method of determining cor-
rect sync slide level by setting it to the mid-point between
sync tip and blanking level at the back porch. This 50% level
is determined by two internal self timing sample and hold cir-
cuits that track sync tip and back porch levels. This also
provides a degree of hum and noise rejection to the input sig-
nal, and compensates for varying input levels of 0.5
P-P
to
2.0V
P-P
.
A built in linear phase, third order, low pass filter attenuates
the chroma signal in color systems to prevent incorrectly set
color burst from disturbing the 50% sync slide.
This device may be used to replace the industry standard
LM1881, offering improved performance and reduced power
consumption.
The EL4581 video sync separator is manufactured using
Elantec’s high performance analog CMOS process.
Features
• NTSC, PAL and SECAM sync separation
• Single supply, +5V
• Precision 50% slicing, internal caps
• Built-in color burst filter
• Decodes non-standard verticals
• Pin compatible with LM1881
• Low power
• Typically 1.5mA supply current
• Resistor programmable scan rate
• Few external components
• Available in 8-pin PDIP and SO packages
Applications
• Video special effects
• Video test equipment
• Video distribution
• Displays
• Imaging
• Video data capture
• Video triggers
Ordering Information
PART
NUMBER
EL4581CN
EL4581CS
TEMP.
RANGE
-40°C to +85°C
-40°C to +85°C
PACKAGE
8-Pin PDIP
8-Pin SO
PKG. NO.
MDP0031
MDP0027
Pinout
EL4581
(8-Pin SO, DIP)
TOP VIEW
COMPOSITE
SYNC OUT
COMPOSITE
VIDEO IN
VERTICAL
SYNC OUT
GND
1
2
3
4
8
7
6
5
VDD 5V
ODD/EVEN OUTPUT
RSET
BURST/BACK
PORCH OUTPUT
Demo Board
A dedicated demo board is not available. However, this
device can be placed on the EL4584/5 Demo Board.
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 321-724-7143
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright © Intersil Americas Inc. 2003. All Rights Reserved. Elantec is a registered trademark of Elantec Semiconductor, Inc.
All other trademarks mentioned are the property of their respective owners. Manufactured under U.S. Patent 5,528,303. Manufactured under License, U.S. Patents 5,486,869; 5,754,250.
1
INTERSIL [ INTERSIL CORPORATION ]
