MAXIM MAX9121, 9122 User Manual

General Description

The MAX9121/MAX9122 quad low-voltage differential sig­naling (LVDS) differential line receivers are ideal for appli­cations requiring high data rates, low power, and low
noise. The MAX9121/MAX9122 are guaranteed to receive
data at speeds up to 500Mbps (250MHz) over controlled­impedance media of approximately 100Ω. The transmis­sion media may be printed circuit (PC) board traces or
cables.

The MAX9121/MAX9122 accept four LVDS differential
inputs and translate them to LVCMOS outputs. The
MAX9122 features integrated parallel termination resis­tors (nominally 107Ω), which eliminate the requirement
for four discrete termination resistors and reduce stub
lengths. The MAX9121 inputs are high impedance and
require an external termination resistor when used in a
point-to-point connection.

The devices support a wide common-mode input range of

0.05V to 2.35V, allowing for ground potential differences
and common-mode noise between the driver and the
receiver. A fail-safe feature sets the output high when the
inputs are open, or when the inputs are undriven and
shorted or parallel terminated. The EN and EN inputs con­trol the high-impedance output. The enables are common
to all four receivers. Inputs conform to the ANSI TIA/EIA­644 LVDS standard. Flow-through pinout simplifies PC
board layout and reduces crosstalk by separating the
LVDS inputs and LVCMOS outputs. The MAX9121/
MAX9122 operate from a single +3.3V supply, and are
specified for operation from -40°C to +85°C. These
devices are available in 16-pin TSSOP and SO packages.
Refer to the MAX9123 data sheet for a quad LVDS line dri­ver with flow-through pinout.

Applications

Digital Copiers

Laser Printers

Cellular Phone Base Stations

Add/Drop Muxes

Digital Cross-Connects

DSLAMs

Network Switches/Routers

Backplane Interconnect

Clock Distribution

____________________________Features

♦ Integrated Termination Eliminates Four External

Resistors (MAX9122)

♦ Flow-Through Pinout

Simplifies PC Board Layout
Reduces Crosstalk

♦ Pin Compatible with DS90LV048A

♦ Guaranteed 500Mbps Data Rate

♦ 300ps Pulse Skew (max)

♦ Conform to ANSI TIA/EIA-644 LVDS Standard

♦ Single +3.3V Supply

♦ Fail-Safe Circuit

MAX9121/MAX9122

Quad LVDS Line Receivers with

Integrated Termination and Flow-Through Pinout

________________________________________________________________ Maxim Integrated Products 1

Typical Application Circuit

19-1909; Rev 0; 6/01

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.

EVALUATION KIT

AVAILABLE

Ordering Information

Pin Configuration appears at end of data sheet.

MAX9123

MAX9122

T

X

T

X

T

X

T

X

R

X

R

X

R

X

R

X

107Ω

107Ω

107Ω

107Ω

100Ω SHIELDED TWISTED CABLE OR MICROSTRIP PC BOARD TRACES

LVDS SIGNALS

LVTTL/LVCMOS
DATA OUTPUT

LVTTL/LVCMOS

DATA INPUT

PART TEMP. RANGE PIN-PACKAGE

MAX9121EUE -40°C to +85°C 16 TSSOP

MAX9121ESE -40°C to +85°C 16 SO

MAX9122EUE -40°C to +85°C 16 TSSOP

MAX9122ESE -40°C to +85°C 16 SO

VCCto GND...........................................................-0.3V to +4.0V

IN_+, IN_- to GND .................................................-0.3V to +4.0V

EN, EN to GND...........................................-0.3V to (V

CC

+ 0.3V)

OUT_ to GND .............................................-0.3V to (V

CC

+ 0.3V)

Continuous Power Dissipation (T

A

= +70°C)

16-Pin TSSOP (derate 9.4mW/°C above +70°C) .........755mW

16-Pin SO (derate 8.7mW/°C above +70°C)................696mW

Storage Temperature Range .............................-65°C to +150°C

Maximum Junction Temperature .....................................+150°C

Operating Temperature Range ...........................-40°C to +85°C

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

ESD Protection

(Human Body Model, IN_+, IN_-) ....................................±8kV

MAX9121/MAX9122

Quad LVDS Line Receivers with
Integrated Termination and Flow-Through Pinout

2 _______________________________________________________________________________________

ABSOLUTE MAXIMUM RATINGS

DC ELECTRICAL CHARACTERISTICS

(VCC= +3.0V to +3.6V, differential input voltage |VID| = 0.1V to 1.0V, common-mode voltage VCM= |VID/2| to 2.4V - |VID/2|,
T

A

= -40°C to +85°C. Typical values are at VCC= +3.3V, TA= +25°C, unless otherwise noted.) (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.

LVDS INPUTS (IN_+, IN_-)

Differential Input High Threshold V

Differential Input Low Threshold V

Input Current (MAX9121) IIN_+, IIN_-

Power-Off Input Current
(MAX9121)

Input Resistor 1 R

Input Resistor 2 R

Differential Input Resistance
(MAX9122)

LVCMOS/LVTTL OUTPUTS (OUT_)

Output High Voltage (Table 1) V

Output Low Voltage V

Output Short-Circuit Current I

Output High-Impedance Current I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

TH

TL

0.1V ≤VID≤ 0.6V -20 20 µA

I

INOFF

R

DIFF

0.6V <V

0.1V ≤VID≤ 0.6V, VCC = 0 -20 20 µA

0.6V <VID≤ 1.0V, VCC = 0 -25 25 µA

V

IN1

IN2

CC

V

CC

V

CC

≤ 1.0V -25 25 µA

ID

= 3.6V or 0, Figure 1 35 kΩ

= 3.6V or 0, Figure 1 132 kΩ

= 3.6V or 0, Figure 1 90 107 132 Ω

IOH = -4.0mA
(MAX9121)

OH

IOH = -4.0mA
(MAX9122)

IOL = +4.0mA, VID = -100mV 0.1 0.25 V

OL

OS

OZ

Enabled, VID = 0.1V, V

Disabled, V

OUT

100 mV

-100 mV

Open, undriven short, or
undriven 100Ω parallel

2.7 3.2

termination

V

= +100mV 2.7 3.2

ID

Open or undriven short 2.7 3.2

= +100mV 2.7 3.2

V

ID

_ = 0 (Note 2) -15 -120 mA

OUT

= 0 or V

CC

-10 +10 µA

V

MAX9121/MAX9122

Quad LVDS Line Receivers with

Integrated Termination and Flow-Through Pinout

_______________________________________________________________________________________ 3

AC ELECTRICAL CHARACTERISTICS

(VCC= +3.0V to +3.6V, CL= 15pF, differential input voltage |VID| = 0.2V to 1.0V, common-mode voltage VCM= |VID/2| to 2.4V ­|V

ID

/2|, input rise and fall time = 1ns (20% to 80%), input frequency = 100MHz, TA= -40°C to +85°C. Typical values are at VCC=

+3.3V, V

CM

= 1.2V, |VID| = 0.2V, TA= +25°C, unless otherwise noted.) (Notes 3, 4)

DC ELECTRICAL CHARACTERISTICS (continued)

(VCC= +3.0V to +3.6V, differential input voltage |VID| = 0.1V to 1.0V, common-mode voltage VCM= |VID/2| to 2.4V - |VID/2|,
T

A

= -40°C to +85°C. Typical values are at VCC= +3.3V, TA= +25°C, unless otherwise noted.) (Note 1)

LOGIC INPUTS (EN, EN)

Input High Voltage V

Input Low Voltage V

Input Current I

SUPPLY

Supply Current I

Disabled Supply Current I

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

IH

IL

IN

CC

CCZ

2.0 V

0 0.8 V

V

= VCC or 0 -15 15 µA

IN_

Enabled, inputs open 9 15 mA

Disabled, inputs open 0.07 0.5 mA

CC

V

Differential Propagation Delay
High to Low

Differential Propagation Delay
Low to High

Differential Pulse Skew [t
t

PLHD

Differential Channel-to-Channel
Skew (Note 6)

Differential Part-to-Part Skew
(Note 7)

Differential Part-to-Part Skew
(Note 8)

Rise-Time t

Fall-Time t

Disable Time High to Z t

Disable Time Low to Z t

Enable Time Z to High t

Enable Time Z to Low t

Maximum Operating Frequency
(Note 9)

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

] (Note 5)

PHLD

t

PHLD

t

PLHD

­t

SKD1

t

SKD2

t

SKD3

t

SKD4

TLH

THL

PHZ

PLZ

PZH

PZL

f

MAX

Figures 2 and 3 1.2 1.93 2.7 ns

Figures 2 and 3 1.2 1.79 2.7 ns

Figures 2 and 3 140 300 ps

Figures 2 and 3 400 ps

Figures 2 and 3 0.8 ns

Figures 2 and 3 1.5 ns

Figures 2 and 3 0.55 1.0 ns

Figures 2 and 3 0.54 1.0 ns

RL = 2kΩ, Figures 4 and 5 14 ns

RL = 2kΩ, Figures 4 and 5 14 ns

RL = 2kΩ, Figures 4 and 5 70 ns

RL = 2kΩ, Figures 4 and 5 70 ns

All channels switching 250 300 MHz

MAX9121/MAX9122

Quad LVDS Line Receivers with
Integrated Termination and Flow-Through Pinout

4 _______________________________________________________________________________________

Typical Operating Characteristics

(VCC= +3.3V, VCM= +1.2V, |VID| = 0.2V, CL= 15pF, TA = +25°C, unless otherwise noted.) (Figures 2 and 3)

40

0

0.01 0.1 1000100

SUPPLY CURRENT

vs. FREQUENCY

10

20

30

MAX9121/22 toc01

FREQUENCY (MHz)

SUPPLY CURRENT (mA)

110

ALL
CHANNELS
SWITCHING

ONE
SWITCHING

7.00

7.50

8.00

8.50

9.00

9.50

10.00

10.50

11.00

-40 -15 10 35 60 85

SUPPLY CURRENT vs.

TEMPERATURE

MAX9121/22 toc02

TEMPERATURE (°C)

SUPPLY CURRENT (mA)

0

10

30

20

40

50

3.0 3.3 3.6

DIFFERENTIAL THRESHOLD VOLTAGE

vs. SUPPLY VOLTAGE

MAX9121/22 toc03

SUPPLY VOLTAGE (V)

DIFFERENTIAL THRESHOLD VOLTAGE (mV)

Note 1: Current into a pin is defined as positive. Current out of a pin is defined as negative. All voltages are referenced to ground

except V

TH

, VTL, and VID.

Note 2: Short only one output at a time. Do not exceed the absolute maximum junction temperature specification.
Note 3: AC parameters are guaranteed by design and characterization.
Note 4: C

L

includes scope probe and test jig capacitance.

Note 5: t

SKD1

is the magnitude difference of differential propagation delays in a channel. t

SKD1

= |t

PHLD

- t

PLHD

|.

Note 6: t

SKD2

is the magnitude difference of the t

PLHD

or t

PHLD

of one channel and the t

PLHD

or t

PHLD

of any other channel on the same part.

Note 7: t

SKD3

is the magnitude difference of any differential propagation delays between parts operating over rated conditions at

the same V

CC

and within 5°C of each other.

Note 8: t

SKD4

is the magnitude difference of any differential propagation delays between parts operating over rated conditions.

Note 9: f

MAX

generator output conditions: rise-time = fall-time = 1ns (0% to 100%), 50% duty cycle, VOH= +1.3V, VOL= +1.1V,

MAX9121/MAX9122 output criteria: 60% to 40% duty cycle, V

OL

= 0.4V (max), VOH= 2.7V (min), load = 15pF.

3.0 3.3 3.6

OUTPUT SHORT-CIRCUIT CURRENT

vs. SUPPLY VOLTAGE

MAX9121/22 toc04

SUPPLY VOLTAGE (V)

OUTPUT SHORT-CIRCUIT CURRENT (mA)

-70

-75

-80

-65

-90

-95

-85

1.30

1.25

1.20

1.15

1.10

3.0 3.3 3.6

OUTPUT HIGH-IMPEDANCE CURRENT

vs. SUPPLY VOLTAGE

MAX9121/22 toc05

SUPPLY VOLTAGE (V)

OUTPUT HIGH-IMPEDANCE CURRENT (nA)

2.7

2.9

3.3

3.1

3.5

3.7

3.0 3.3 3.6

OUTPUT HIGH VOLTAGE vs.

SUPPLY VOLTAGE

MAX9121/22 toc06

SUPPLY VOLTAGE (V)

OUTPUT HIGH VOLTAGE (V)

AC ELECTRICAL CHARACTERISTICS (continued)

(VCC= +3.0V to +3.6V, CL= 15pF, differential input voltage |VID| = 0.2V to 1.0V, common-mode voltage VCM= |VID/2| to 2.4V ­|V

ID

/2|, input rise and fall time = 1ns (20% to 80%), input frequency = 100MHz, TA= -40°C to +85°C. Typical values are at VCC=

+3.3V, V

CM

= 1.2V, |VID| = 0.2V, TA= +25°C, unless otherwise noted.) (Notes 3, 4)