Maxim MAX3762E-D, MAX3761EEP, MAX3761E-D Datasheet

_______________General Description

The MAX3761/MAX3762 limiting amplifiers, with 4mV
sensitivity and PECL data outputs, are optimized for
operation in low-cost, 622Mbps, LAN/ATM LAN fiber
optics applications.

An integrated power detector senses the input signal’s
amplitude. A received-signal-strength indicator (RSSI)
gives an analog indication of the power level, while the
complementary loss-of-signal (LOS) outputs indicate if
the input power level exceeds the programmed
threshold level. The LOS threshold can be adjusted to
detect signal amplitudes between 3mVp-p and
100mVp-p, providing a 15dB LOS adjustment in fiber
optic receivers. The LOS outputs have 3.5dB of
hysteresis, which prevents chatter when input signal
levels are small. The MAX3761’s LOS outputs are com­patible with TTL-logic levels. The MAX3762 has PECL
LOS outputs.

DISABLE and LOS can be used to implement a squelch
function, which turns off the data outputs when the
input signal is below the programmed threshold.

________________________Applications

622Mbps LAN/ATM LAN Receivers
155Mbps LAN/ATM LAN Receivers

____________________________Features

♦ Chatter-Free Power Detector with Programmable

Loss-of-Signal Outputs

♦ 4mV Input Sensitivity (PECL Loss-of-Signal

Interface Logic—MAX3766

♦ PECL Data Outputs
♦ Single 5V Power Supply
♦ 250ps Output Edge Speed
♦ Low 15ps Pulse-Width Distortion
♦ TTL Loss-of-Signal Interface Logic—MAX3761

MAX3761/MAX3762

Low-Power, 622Mbps Limiting Amplifiers

with Chatter-Free Power Detect for LANs

________________________________________________________________

Maxim Integrated Products

1

CZN

OUT+

OUT-

LOS-

LOS+

DISABLE

SUB

GND

GNDO

100pF

50Ω

CZP

R1

100k

R2

22k

+V

CC

VTH

INV

MAX3761

CAZ
150pF

50Ω

V

CC

- 2V

V

CC

EN
RSSI

VCCO

VIN+

10nF

100pF
BYPASS
SUPPLY

C

IN



5.6nF

C

IN



5.6nF

+5V

VIN­FILTER

C

FILTER

_________Typical Operating Circuits

19-1097; Rev 1; 9/96

PART

MAX3761EEP

MAX3761C/D
MAX3762EEP

-40°C to +85°C

-40°C to +85°C

-40°C to +85°C

TEMP. RANGE PIN-PACKAGE

20 QSOP
Dice*
20 QSOP

EVALUATION KIT

AVAILABLE

______________Ordering Information

*

Dice are designed to operate from -40°C to +85°C, but are

tested and guaranteed only at TA= +25°C.

For free samples & the latest literature: http://www.maxim-ic.com, or phone [phone]

MAX3762C/D -40°C to +85°C Dice*

__________________Pin Configuration

20
19
18
17
16
15
14
13

1
2
3
4
5
6
7
8

DISABLE
LOS+
LOS­V

CC

V

CC

EN

RSSI

FILTER

TOP VIEW

VCCO
OUT+
OUT­GNDO

SUB

GND

VIN-

VIN+

12
11

9

10

VTH
INV

CZN

CZP

QSOP

MAX3761
MAX3762



MAX3762 at end of data sheet.

MAX3761/MAX3762

Low-Power, 622Mbps Limiting Amplifiers
with Chatter-Free Power Detect for LANs

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(VCC= +4.5V to +5.5V, DISABLE = low, TA= -40°C to +85°C, unless otherwise noted. Typical values are at VCC= +5.0V, TA= +25°C.)
(Note 1)

Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.

Note 1: Dice are tested at TA = +25°C.
Note 2: Outputs terminated with 50Ω to V

CC

- 2V.

Note 3: Voltage measurements are relative to V

CC

.

V

CC

, VCCO............................................................-0.5V to +7.0V

FILTER, RSSI, EN, VIN+, VIN-, CZP, CZN,

DISABLE, LOS+, LOS-, INV, VTH...............-0.5V to (V

CC

+ 0.5V)

PECL Output Current (OUT+, OUT-, LOS+, LOS-) ............50mA

Continuous Power Dissipation (T

A

= +85°C)

QSOP (derate 8.3mW/°C above +70°C).......................667mW

Operating Junction Temperature Range...........-40°C to +150°C

Processing Temperature (die).........................................+400°C

Storage Temperature Range.............................-65°C to +160°C

Lead Temperature (soldering, 10sec).............................+300°C

MAX3762, I

VCC

MAX3761, I

VCC

DISABLE = high

DISABLE = high

MAX3761

MAX3761

(Notes 2, 3)

(Notes 2, 3)

Logic high

MAX3762 (Notes 2, 3)

MAX3761
MAX3761

MAX3762 (Note 3)

MAX3762 (Notes 2, 3)

MAX3762 (Note 3)

CONDITIONS

VVCC- 0.7 VCC-1.2Disabled Common-Mode Output

mV-100 100Disabled Differential Output

mV-1830 -1555PECL Data Output Voltage Low (VOL)

mV-1150 -880PECL Data Output Voltage High (VOH)

mV-1470DISABLE Input PECL Low

mV-1160DISABLE Input PECL High

mA

30 46

25 37

Power-Supply Current

V0.8DISABLE Input Low

V2.65DISABLE Input High

µA100DISABLE Input Current

mV-1830 -1555LOS Output PECL Low

V2.8LOS Output TTL High
V

0.40

LOS Output TTL Low

mV-1150 -880LOS Output PECL High

UNITSMIN TYP MAXPARAMETER

(TA= +25°C to +85°C)
(TA= -40°C to +25°C) 0.44

MAX3761/MAX3762

Low-Power, 622Mbps Limiting Amplifiers

with Chatter-Free Power Detect for LANs

_______________________________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS

(VCC= +4.5V to +5.5V, PECL outputs terminated with 50Ω to VCC- 2V, input 4mV to 2Vp-p, TA= -40°C to +85°C, unless otherwise
noted. Typical values are at V

CC

= +5.0V, TA = +25°C.) (Note 5)

Note 5: AC parameters are guaranteed by design and characterization.
Note 6: Input signal is a 1-0 pattern, 622Mbps.
Note 7: PWD = [(width of wider pulse) - (width of narrower pulse)] / 2.

TA= -40°C, 2

23

- 1 PRBS

(Notes 6, 7)

(Note 6)

Differential

20% to 80%

CONDITIONS

Ω3900Input Resistance

psPulse-Width Distortion

mV3.2Minimum LOS Assert Input

15 80

%20Data-Output Overshoot

ps250Data-Output Edge Speed

UNITSMIN TYP MAXPARAMETER

__________________________________________Typical Operating Characteristics

(MAX3761/MAX3762 EV kit, VCC= +5.0V, PECL outputs terminated with 50Ωto VCC- 2V, input is a 1-0 pattern, 622Mbps, TA= +25°C,
unless otherwise noted.)

10

15

20

25

30

35

40

45

50

-40 -15 10 35 60 85

MAX3762

SUPPLY CURRENT vs. TEMPERATURE

MAX3761/62-01

AMBIENT TEMPERATURE (°C)

CURRENT (mA)

VCC = 5.5V

VCC = 5.0V

VCC = 4.5V

10 100 10001

INPUT SIGNAL (mVp-p)

RSSI VOLTAGE (V)

2.40

2.16

1.68

1.44

1.20

1.92

2.28

1.80

1.56

1.32

2.04

RSSI vs. INPUT AMPLITUDE

AND DATA PATTERN

MAX3761/62-02

2

23

- 1

PRBS PATTERN

1-0 PATTERN

2.40

1.20

-50 -40 -20 0

RSSI vs.

INPUT POWER AND FREQUENCY

1.44

2.16

MAX3761/62-03

INPUT POWER (dBm)

RSSI VOLTAGE (V)

-30 -10-45 -25 -5-35 -15

1.92

1.68

1.32

1.56

2.28

2.04

1.80

10MHz

500MHz

2

23

- 1 PRBS, VTH = 1.8V dB3.5LOS Hysteresis

100mV/

div

5µs/div

LOS OPERATION 

WITH SQUELCHING

MAX3761/62-10

DATA IN

LOS+

OUT+

MAX3761/MAX3762

Low-Power, 622Mbps Limiting Amplifiers
with Chatter-Free Power Detect for LANs

4 _______________________________________________________________________________________

2.00

1.20

-40 -20 800 204060

RSSI vs. TEMPERATURE
(622Mbps 2

23

- 1 PRBS)



1.36

1.84

MAX3761/62-04

AMBIENT TEMPERATURE (°C)

RSSI VOLTAGE (V)

1.68

1.52

1.28

1.44

1.92

1.76

1.60

VIN = 50mVp-p

VIN = 16mVp-p

VIN = 4mVp-p

2.50

2.75

3.00

3.25

3.50

3.75

4.00

-40

-20

0 20406080100

LOS HYSTERESIS vs. TEMPERATURE

(622Mbps 2

23

- 1 PRBS PATTERN)

MAX3761/62-05

AMBIENT TEMPERATURE (°C)

HYSTERESIS (dB)

ASSERT LEVEL SET

TO APPROXIMATELY

2mVp-p

ASSERT LEVEL SET

TO APPROXIMATELY 30mVp-p

3

4

5

6

7

8

-40 0-20 20 40 60

80

100

LOS HYSTERESIS vs. TEMPERATURE

(622Mbps 1-0 PATTERN)

MAX3761/62-06

AMBIENT TEMPERATURE (°C)

HYSTERESIS (dB)

ASSERT LEVEL SET

TO APPROXIMATELY

2mVp-p

ASSERT LEVEL SET

TO APPROXIMATELY

30mVp-p

-0.8

-1.8

-40 -20

0

20 40 60 80

DATA OUTPUT LEVELS

(REFERENCE TO V

CC

)

-1.6

-1.0

MAX3761/62-07

AMBIENT TEMPERATURE (°C)

VOLTAGE (V)

-1.2

-1.4

VOH

VOL

1m 1010.10.01

INPUT SIGNAL (Vp-p)

DIFFERENTIAL OUTPUT (mV)

1400
1280
1160

0.1m

1040

800
680
560
440

200

320

920

DIFFERENTIAL OUTPUT

vs. INPUT AMPLITUDE

MAX3761/62-08

0.01 0.1 1 100.001
INPUT SIGNAL (Vp-p)

PULSE-WIDTH DISTORTION (PS)

50

40

20

10

0

30

PULSE-WIDTH DISTORTION

(622Mbps DATA RATE)

MAX3761/62-09

-40°C

+85°C

100mV/

div

5µs/div

DATA IN

LOS+

OUT+

LOS OPERATION 

WITHOUT SQUELCHING

MAX3761/62-11

50mV/

div

500ps/div

DATA OUTPUT SINGLE-ENDED

(2

23

- 1 PRBS PATTERN)

MAX3761/62-12

INPUT = 4mVp-p
T

A

= +85°C

____________________________Typical Operating Characteristics (continued)

(MAX3761/MAX3762 EV kit, VCC= +5.0V, PECL outputs terminated with 50Ωto VCC- 2V, input is a 1-0 pattern, 622Mbps, TA= +25°C,
unless otherwise noted.)