FN7172 Rev 2.00

Page 1 of 10

November 12, 2010

FN7172

Rev 2.00

November 12, 2010

EL4581

Sync Separator, 50% Slice, S-H, Filter

DATASHEET

The EL4581 extracts timing information from standard

negative going video sync found in NTSC, PAL and SECAM

broadcast systems. It can also be used in non standard

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

interlaced scan formats.

The EL4581 provides a reliable method of determining

correct 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

circuits that track sync tip and back porch levels. This also

provides a degree of hum and noise rejection to the input

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.

Pinout

EL4581

(8 LD SOIC, PDIP)

TOP VIEW

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 Ld PDIP and SOIC packages

• Pb-free available (RoHS compliant)

Applications

• Video special effects

• Video test equipment

• Video distribution

• Displays

•Imaging

• Video data capture

• Video triggers

Demo Board

A dedicated demo board is not available. However, this

device can be placed on the EL4584/5 Demo Board.

1

2

3

4

8

7

6

5

COMPOSITE

SYNC OUT

COMPOSITE

VIDEO IN

VERTICAL

SYNC OUT

GND

VDD 5V

ODD/EVEN OUTPUT

RSET

BURST/BACK

PORCH OUTPUT

Ordering Information

PART

NUMBER

PART

MARKING

TEMP. RANGE

PACKAGE

PKG.

DWG. #

EL4581CN

EL4581CN

-40°C to +85°C 8 Ld PDIP

MDP0031

EL4581CS*

4581CS

-40°C to +85°C 8 Ld SOIC

MDP0027

EL4581CSZ*

(Note)

4581CSZ

-40°C to +85°C 8 Ld SOIC

(Pb-free)

MDP0027

*Add “-T7” or “-T13” suffix for tape and reel. Please refer to TB347 for

details on reel specifications.

NOTE: These Intersil Pb-free plastic packaged products employ special

Pb-free material sets; molding compounds/die attach materials and 100%

matte tin plate PLUS ANNEAL - e3 termination finish, which is RoHS

compliant and compatible with both SnPb and Pb-free soldering

operations. Intersil Pb-free products are MSL classified at Pb-free peak

reflow temperatures that meet or exceed the Pb-free requirements of

IPC/JEDEC J STD-020.