Data Sheet

February 1999

LG1605DXB Limiting Amplifier

Features

s

28 dB gain, 34 dB differential

s

Large dynamic range: >60 dB

s

Wideband response: 8 kHz to 3 GHz

s

Extremely low ±4 ps delay skew across input range

s

Complementary 50

Ω I/Os

s

Surface-mount package

s

Standard ECL supply (400 mW)

Applications

s

Data/clock main amplifier SONET/SDH OC-48/

STM-16 transmission systems, DWDM systems

s

Digital video transmission

s

Interface between 1319 receiver and LG1600

clock and data regenerator

s

High-speed comparator

Functional Description

The LG1605DXB is a GaAs wideband limiting ampli-

fier with differential inputs and outputs that provides

28 dB of gain (34 dB differential) and 3 GHz of band-

width in a 50

Ω environment (Figure 1 shows the

block diagram). At low input levels, below 10 mV to

20 mV, the circuit behaves as a linear amplifier. At

higher levels, the device goes smoothly into limiting.

The device matches the performance of an AGC

amplifier but shows none of the AGC bouncing and

attack characteristics.

12-3214(F).r3

Figure 1. LG1605DXB Block Diagram

110 pF

25 k

Ω

110 pF

–+

13

14

2

3

CHIP BOUNDARY

GND

1, 4, 5, 6, 15, 16

7

8

+

–

–

+

9

10

11

12

110 pF

50

Ω

25 k

Ω

+

–

–

+

50

Ω