MOTOROLA

SEMICONDUCTOR TECHNICAL DATA

1

REV 1

5/96

622Mb/s Fiber Optic Post

Amplifier

The SX1125 is an integrated limiting amplifier for high frequency fiber

optic applications. The device interfaces directly to the trans–impedance

amplifier of a typical optical to electrical conversion portion of a fiber optic

link. With data rate capabilities in the 622Mb/s range, the high gain

limiting amplification of the SX1125 is ideal for high speed fiber optic

applications like SONET/SDM, ATM, FDDI, Fibre Channel or Serial Hippi.

The device is functionally and pin compatible to the Signetics SA5225

with a significantly higher bandwidth. The CAZP and CAZN inputs to the

limiting amplifier provide an auto-zero function to effectively cancel any

input offset voltage present in the amplifier.

The SX1125 incorporates a programmable level detect function to

identify when the input signal has been lost. This information can be fed

back to the Disable input of the device to maintain stability under loss of

signal conditions. Using the Vset pin the sensitivity of the level detect can

be adjusted. The CLD input is used to filter the level detect input so that

random noise spikes are filtered out.

The MC10SX1125 is compatible with MECL10H logic levels.

BLOCK DIAGRAM

LOS

LOS

Dout

Dout

Reference

ECL

Buffer

Level

Detect

Limiting

Amplifier

ECL

Buffer

Disable

Disable

CLD

Din

Din

Vref

Vset

CAZP CAZN

15

16

14

13

12

11

10

2

1

34567

Vset

9

8

Vref VCCE Dout Dout GNDE LOS

LOS

CAZN CAZP GNDA Din

Din VCCA CLD Disable

Pinout: 16-Lead Plastic Package

(Top View)

MC10SX1125

FIBER OPTIC

POST AMPLIFIER

D SUFFIX

PLASTIC SOIC PACKAGE

CASE 751B-05