General Description

The MAX3645 limiting amplifier functions as a data

quantizer and is pin compatible with the Mindspeed

MC2045-2 and MC2045-2Y postamplifiers. The amplifi-

er accepts a wide range of input voltages and provides

constant-level positive emitter-coupled logic (PECL)

output voltages with controlled edge speeds.

The MAX3645 features an integrated power detector

with complementary PECL loss-of-signal (LOS) outputs

that indicate when the input power level drops below a

programmable threshold. An optional squelch function

holds the data outputs at static levels during a

LOS condition.

The MAX3645 operates from a single +3.3V or +5.0V

power supply over a -40

°C to +85°C temperature

range. It is available in 16-pin SO and 16-pin QSOP

packages.

Applications

SONET 155Mbps Transceivers

Fast Ethernet Receivers

FDDI 125Mbps Receivers

FTTx Receivers

ESCON Receivers

Features

♦ Pin Compatible with the Mindspeed

MC2045-2/MC2045-2Y

♦ Compatible with 4B/5B Data Coding

♦ Programmable LOS Threshold

♦ Stable LOS Threshold Over Supply Range

♦ Output Disable Function and Automatic Squelch

♦ Single +3.3V or +5.0V Power Supply

♦ 18mA Supply Current

+2.97V to +5.5V, 125Mbps to 200Mbps Limiting

Amplifier with Loss-of-Signal Detector

________________________________________________________________ Maxim Integrated Products

1

Ordering Information

19-3026; Rev

1; 11/04

For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at

1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.

PART

TEMP RANGE

PIN-PACKAGE

MAX3645ESE

-40°C to +85°C

16 SO

MAX3645EEE

-40

°C to +85°C

16 QSOP

MAX3645EEE+

-40

°C to +85°C

16 QSOP

16

15

14

13

12

11

10

9

1

2

3

4

5

6

7

8

CAZ2

TH

N.C.

DOUT+

DOUT-

GNDE

LOS

TOP VIEW

MAX3645

SO/QSOP

CAZ1

GNDA

DIN+

DIN-

CSD

DIS

LOS

Pin Configuration

MAX3645

MAX3644*

PIN K

IN

OUT-

OUT+

DIN+

DIN-

GNDA

DOUT+

DOUT-

LOS

LOS

DIS

CAZ2

GND

*FUTURE PRODUCT

TH

GNDE

N.C.

0.1

µF

0.1

µF

1nF

0.1

µF

100

Ω

50

Ω

50

Ω

50

Ω

50

Ω

Typical Application Circuit

+Denotes lead-free package.