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LTC1520

50Mbps Precision Quad

Line Receiver

May 1996

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.

However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-

tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.

Final Electrical Specifications

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Precision Propagation Delay: 18ns

±3ns Over

Temperature

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Data Rate: 50Mbps

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Low Channel-to-Channel Skew: 400ps Typ

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Rail-to-Rail Input Common Mode Range

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High Input Resistance:

≥18k, Even When Unpowered

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Hot Swap Capable

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Can Withstand Input DC Levels of

±10V

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Short-Circuit Protected

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Single 5V Supply

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LVDS Compatible

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Will Not Oscillate with Slow Input Signals

FEATURES

The LTC

receiver that can operate at data rates as high as 50Mbps.

A unique architecture provides very stable propagation

delays and low skew over a wide input common mode,

input overdrive and ambient temperature range. Propaga-

tion delay is 18ns

500ps and channel-to-channel skew is 400ps.

100mV) into valid CMOS and TTL output levels. Its high

input resistance (

≥18k) allows many receivers to be con-

nected to the same driver. The receiver outputs go into a

high impedance state when disabled.

Protection features include thermal shutdown and a con-

trolled maximum short-circuit current (50mA max) that

does not oscillate in and out of short-circuit mode. Input

resistance remains

≥18k when the device is unpowered or

disabled, thus allowing the LTC1520 to be hot swapped into

a backplane without loading the data lines.

The LTC1520 operates from a single 5V supply and draws

12mA of supply current. The part is available in a 16-lead

narrow SO package.

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High Speed Backplane Interface

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Line Collision Detector

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PECL and LVDS Line Receivers

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Level Translator

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Ring Oscillator

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Tapped Delay Line

, LTC and LT are registered trademarks of Linear Technology Corporation.

High Speed Backplane Receiver

Propagation Delay Guaranteed to Fall

Within Shaded Area (

±3ns)

–

+

–

+

–

+

–

+

LTC1520

LTC1520 TA01

3.3k

5V

3.3k

0.01

µF

LTC1520 TA02

1V/DIV

5V/DIV

–5

5

15

TIME (ns)

25

35

0

10203040 45

RECEIVER

INPUT

RECEIVER

OUTPUT