MAXIM MAX3800 Technical data

General Description

The MAX3800 is a +3.3V adaptive cable equalizer and
cable driver implemented together on a single chip. It is
designed for coaxial and twin-axial cable point-to-point
communications applications. The driver features differ­ential current-mode logic (CML) inputs and outputs as
well as adjustable output amplitude. The equalizer
includes differential CML data inputs and outputs, a
loss-of-signal (LOS) output, and a cable integrity moni­tor (CIM) output.

The adaptive cable equalizer is capable of equalizing
differential or single-ended signals at data rates up to

3.2Gbps. It automatically adjusts to attenuation caused
by skin-effect losses of up to 30dB at 1.6GHz. The
equalizer effectively extends the usable length of cop­per cable in high-frequency interconnect applications.

The MAX3800 is available in a 32-pin TQFP package
with exposed pad and consumes only 200mW at
+3.3V. The driver can be disconnected from the power
supply when it is not needed, resulting in a 40% reduc­tion in supply current.

Applications

High-Speed Links in Communications
and Data Systems

Backplane and Interconnect Applications

SDH/SONET Transmission Equipment

Features

♦ Single +3.3V Operation

♦ Typical Power Dissipation = 200mW at +3.3V

♦ Data Rates Up to 3.2Gbps

♦ Adjustable Cable Driver Output Amplitude

♦ Equalizer Automatically Adjusts for Different

Cable Lengths

♦ 0dB to 30dB Equalization at 1.6GHz (3.2Gbps)
♦ Loss-of-Signal (LOS) Indicator

♦ Cable Integrity Monitor (CIM)

♦ On-Chip Input and Output Terminations

♦ Low External Component Count
♦ Operating Temperature Range = 0°C to +85°C

♦ ESD Protection on Cable Inputs and Outputs

MAX3800

3.2Gbps Adaptive Equalizer
and Cable Driver

________________________________________________________________ Maxim Integrated Products 1

Ordering Information

DOUT

EIN

DIN

EOUT

MAX3800

DOUT

EIN

DIN

THIS SYMBOL INDICATES A CONTROLLED-IMPEDANCE TRANSMISSION LINE.

EOUT

RMOD CIM

MAX3800

CARD 2

CARD 1

+3.3V

+3.3V

LOS RMOD CIMLOS

Typical Application Circuit

19-1953; Rev 3; 12/05

PART

TEMP

RANGE

PIN­PACKAGE

PKG

CODE

MAX3800UGJ

32 QFN

G3255-1

MAX3800UHJ

AA-EP

MAX3800UHJ+

AA-EP

*EP = exposed pad
+Denotes lead-free package.

Pin Configuration appears at end of data sheet.

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.

0°C to +85°C
0°C to +85°C
0°C to +85°C

32 TQFP-EP*

32 TQFP-EP*

MAX3800

3.2Gbps Adaptive Equalizer
and Cable Driver

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(VCC= +3.14V to +3.46V, TA= 0°C to +85°C. Typical values are at VCC= +3.3V and TA= +25°C, unless otherwise noted.)

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.

Supply Voltage, VCC..............................................-0.5V to +6.0V

Voltage at LOS, RMOD, and CIM...............-0.5V to (V

CC

+ 0.5V)

Voltage at EIN+, EIN-, DIN+, DIN- .....(V

CC

- 1V) to (VCC+ 0.5V)

Current Out of EOUT+, EOUT-, DOUT+, DOUT- ................25mA

Continuous Power Dissipation (T

A

= +85°C)

32-Pin TQFP-EP (derate 22.2mW/°C above +85°C) ...1444mW

Operating Ambient Temperature Range ................0°C to +85°C

Storage Temperature Range .............................-55°C to +150°C

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

PARAMETER

CONDITIONS

UNITS

Supply Current I

CC

Includes external load current (Note 1) 65 85 mA

CABLE DRIVER INPUT SPECIFICATIONS

Input Voltage (Single-Ended)

V

DIN+,

V

DIN-

V

Input Voltage (Differential) V

DIN

V

DIN

= (V

DIN+

) - (V

DIN-

)

mVp-p

Input Impedance Single-ended 45 55 65 Ω

CABLE DRIVER OUTPUT SPECIFICATIONS

R

MOD

= 10kΩ (Note 2)

mVp-p

Output Voltage
(Differential)

R

MOD

= 20kΩ (Note 2)

550

mVp-p

Output Impedance Single-ended 50

75 Ω

CABLE EQUALIZER INPUT SPECIFICATIONS

M i ni m um C ab l e Inp ut ( D i ffer enti al )

700

mVp-p

M axi m um C ab l e Inp ut ( D i ffer enti al )

mVp-p

Input Impedance Single-ended 45 55 65 Ω

CABLE EQUALIZER OUTPUT SPECIFICATIONS

Output Voltage (Differential) (Note 2)

mVp-p

Output Impedance Single-ended 50

75 Ω

V ol tag e at C IM Outp ut ( D i ffer enti al )

V

CIM

No external load, V

CIM

= (V

CIM+

) - (V

CIM-

)

Vp-p

Voltage at CIM Output
(Single-Ended)

V

CIM+,

V

CIM-

No external load 0.5

V

Output high (Note 4) 2.4 V

Voltage at LOS

Output low (Note 4) 0.4 V

Outp ut C om m on- M od e V ol tag e Each output DC-coupled 50Ω to V

CC

V

CC

- 0.2 V

SYMBOL

MIN TYP MAX

V

CC

- 0.6

400 1100

750 870 1000

400 450

62.5

3.2Gbps, 30dB cable loss at 1.6GHz (Note 3) 650

1100

500 1000

62.5

-0.5 +0.5

V

CC

+ 0.2

V

CC

- 0.5

MAX3800

3.2Gbps Adaptive Equalizer
and Cable Driver

_______________________________________________________________________________________ 3

Note 1: Equalizer and driver total currents (equalizer with maximum equalization and driver with maximum output swing).
Note 2: Input voltage within specification limits, 50Ω to V

CC

at each output.

Note 3: Minimum cable input for LOS to assert high.
Note 4: 100kΩ load to ground.
Note 5: AC electrical characteristics are guaranteed by design and characterization.

Note 6: V

DIN

= 400mVp-p to 1100mVp-p (differential), 10kΩ≤RMOD ≤ 20kΩ, 3.2Gbps 213-1 PRBS with 100 consecutive ones and

100 consecutive zeros substituted.

Note 7: Includes random jitter and deterministic jitter.
Note 8: Differential cable input voltage = 700mVp-p, 3.2Gbps 213-1 PRBS with 100 consecutive ones and 100 consecutive zeros

substituted. Cable loss is due to skin effect only.

AC ELECTRICAL CHARACTERISTICS

(VCC= +3.14V to +3.46V, TA= 0°C to +85°C. Typical values are at VCC= +3.3V and TA= +25°C, unless otherwise noted.) (Note 5)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Maximum Input Data Rate 3.2

Gbps

CABLE DRIVER SPECIFICATIONS

Random Jitter (Note 6) 2 4

mUI

RMS

Deterministic Jitter (Note 6) 20 60

mUIp-p

Output Edge Speed 20% to 80% 59 76 ps

Input Return Loss (Single-Ended)

≤3.2GHz 14 dB

Outp ut Retur n Loss ( S i ng l e- E nd ed )

≤3.2GHz 14 dB

EQUALIZER SPECIFICATIONS

0dB cable loss (Note 8)

mUIp-p

24dB cable loss (Note 8) 97

mUIp-p

Residual Jitter (Note 7)

30dB cable loss (Note 8)

mUIp-p

Output Edge Speed 20% to 80% 56 77 ps

Input Return Loss (Single-Ended)

≤3.2GHz 14 dB

Outp ut Retur n Loss ( S i ng l e- E nd ed )

≤3.2GHz 14 dB

Equalization Compensation 1.6GHz (skin-effect losses only) 30 dB

Equalization Time Constant 5µs

170 240

200

112 200

MAX3800

3.2Gbps Adaptive Equalizer
and Cable Driver

4 _______________________________________________________________________________________

20

30

25

40

35

50

45

55

65

60

70

020304010 50 60 70 80 90

SUPPLY CURRENT vs. TEMPERATURE

MAX3800 toc01

TEMPERATURE (°C)

SUPPLY CURRENT (mA)

DRIVER + EQUALIZER

EQUALIZER

DRIVER

400

600

500

900

800

700

1200

1100

1000

1300

410713161922

CABLE DRIVER OUTPUT VOLTAGE vs. RMOD

MAX3800 toc02

R

MOD

(kΩ)

DRIVER OUTPUT VOLTAGE (mV)

-50

-30

-40

-10

-20

10

0

20

40

30

50

0 0.8 1.2 1.60.4 2.0 2.4 2.8 3.63.2 4.0

DRIVER INPUT RETURN LOSS (S11)

MAX3800 toc03

FREQUENCY (GHz)

GAIN (dB)

-50

-30

-40

-10

-20

10

0

20

40

30

50

0 0.8 1.2 1.60.4 2.0 2.4 2.8 3.63.2 4.0

DRIVER OUTPUT RETURN LOSS (S22)

MAX3800 toc04

FREQUENCY (GHz)

GAIN (dB)

30

35

45

40

50

55

0.001 0.10.01 1 10 100

EQUALIZER RESIDUAL JITTER vs. POWER SUPPLY

NOISE (100mVp-p SINE WAVE) (40FT OF MADISON

#14887 SHIELDED TWISTED PAIR-DIFFERENTIAL)

MAX3800 toc05

NOISE FREQUENCY (MHz)

JITTER (ps

p-p

)

40

60

50

80

70

100

90

110

40 50 5545 60 65 70 75 80 85 (INCHES)

EQUALIZER RESIDUAL JITTER vs. LINE LENGTH

(FR-4 6MIL STRIPLINE - SINGLE-ENDED)

MAX3800 toc09

LINE LENGTH

JITTER (ps

p-p

)

3.2Gbps

622Mbps

2.5Gbps

1.02 1.27 1.401.14 1.52 1.65 1.77 1.90 2.03 2.16 (METERS)

20

30

40

50

60

70

80

90

100

10 20 30 40 50 (FEET)

EQUALIZER RESIDUAL JITTER vs.

CABLE LENGTH (MADISON #13887 SHIELDED

TWISTED PAIR-DIFFERENTIAL)

MAX3800 toc07

CABLE LENGTH

JITTER (ps

p-p

)

3.2Gbps
622Mbps

2.5Gbps

3.05 6.1 9.14 12.19 15.24 (METERS)

40

80

60

120

100

140

160

25 55 6535 45 75 85 95 (FEET)

EQUALIZER RESIDUAL JITTER vs.

CABLE LENGTH (RG179B 75Ω COAXIAL

CABLE - SINGLE-ENDED)

MAX3800 toc08

CABLE LENGTH

JITTER (ps

p-p

)

3.2Gbps

622Mbps

2.5Gbps

7.65 16.76 19.8110.67 13.72 22.86 25.91 28.96 (METERS)

70

80

100

90

120

130

110

140

300 500 600400 700 800 900 1000 1100

EQUALIZER RESIDUAL JITTER vs. CABLE

INPUT AMPLITUDE (RG179B 75Ω

COAXIAL CABLE - SINGLE-ENDED)

MAX3800 toc06

CABLE INPUT AMPLITUDE (mV)

JITTER (ps

p-p

)

25 FT

72 FT

Typical Operating Characteristics

(TA = +25°C, VCC= +3.3V, all jitter measurements done at 3.2Gbps, 700mV cable input with 213-1 PRBS pattern with 100 consecutive
ones and 100 consecutive zeros substituted. Note: Test pattern produces near worst-case jitter results. Results will vary with pattern,
unless otherwise noted.)