19-1550; Rev 6; 11/04
3.0V to 5.5V, 1.25Gbps/2.5Gbps
LAN Laser Drivers
General Description
The MAX3286/MAX3296 series of products are high-
speed laser drivers for fiber optic LAN transmitters opti-
mized for Gigabit Ethernet applications. Each device
contains a bias generator, laser modulator, and com-
prehensive safety features. Automatic power control
(APC) adjusts the laser bias current to maintain aver-
age optical power at a constant level, regardless of
changes in temperature or laser properties. For lasers
without a monitor photodiode, these products offer a
constant-current mode. The circuit can be configured
for use with conventional shortwave (780nm to 850nm)
or longwave (1300nm) laser diodes, as well as vertical-
cavity surface-emitting lasers (VCSELs).
The MAX3286 series (MAX3286–MAX3289) is opti-
mized for operation at 1.25Gbps, and the MAX3296
series (MAX3296–MAX3299) is optimized for 2.5Gbps
operation. Each device can switch 30mA of laser mod-
ulation current at the specified data rate. Adjustable
temperature compensation is provided to keep the opti-
cal extinction ratio within specifications over the operat-
ing temperature range. This series of devices is
optimized to drive lasers packaged in low-cost TO-46
headers. Deterministic jitter (DJ) for the MAX3286 is
typically 22ps, allowing a 72% margin to Gigabit
Ethernet DJ specifications.
These laser drivers provide extensive safety features to
guarantee single-point fault tolerance. Safety features
include dual enable inputs, dual shutdown circuits, and
a laser-power monitor. The safety circuit detects faults
that could cause dangerous light output levels. A pro-
grammable power-on reset pulse initializes the laser
driver at startup.
The MAX3286/MAX3296 are available in a compact, 5mm
✕
5mm, 28-pin QFN or thin QFN package; a 5mm
✕
5mm,
32-pin TQFP package; or in die form. The MAX3287/
MAX3288/MAX3289 and MAX3297/MAX3298/MAX3299
are available in a 16-pin TSSOP-EP package.
Features
♦
7ps Deterministic Jitter (MAX3296)
22ps Deterministic Jitter (MAX3286)
♦
+3.0V to +5.5V Supply Voltage
♦
Selectable Laser Pinning (Common Cathode or
Common Anode) (MAX3286/MAX3296)
♦
30mA Laser Modulation Current
♦
Temperature Compensation of Modulation Current
♦
Automatic Laser Power Control or Constant
Bias Current
♦
Integrated Safety Circuits
♦
Power-On Reset Signal
♦
QFN and Thin QFN Packages Available
MAX3286–MAX3289/MAX3296–MAX3299
Ordering Information
PART
MAX3286CTI+
MAX3286CGI
MAX3286CHJ
TEMP RANGE
0°C to +70°C
0°C to +70°C
0°C to +70°C
PIN-PACKAGE
28 Thin QFN
(5mm x 5mm)****
28 QFN
(5mm x 5mm)***
32 TQFP
(5mm x 5mm)
Ordering Information continued at end of data sheet.
*Dice
are designed to operate from T
J
= 0°C to +110°C, but
are tested and guaranteed only at T
A
= +25°C.
**Exposed
pad.
***Package
Code: G2855-1
****Package
Code: T2855-7
+Denotes
Lead-Free Package.
Pin Configurations
OUT+
OUT-
V
CC
V
CC
28
TC
27
26
25
24
23
Applications
Gigabit Ethernet Optical Transmitter
Fibre Channel Optical Transmitter
ATM LAN Optical Transmitter
FAULT
FAULT
POR
GND
EN
EN
PORDLY
1
2
3
4
5
6
7
+
22
V
CC
TOP VIEW
MODSET
21
20
19
BIASDRV
SHDNDRV
GND
MON
MD
POL
POL
MAX3286
MAX3296
18
17
16
15
10
11
12
13
GND
FLTDLY
LV
IN+
V
CC
IN-
Typical Application Circuits and Selector Guide appear at
end of data sheet.
THIN QFN*
*Exposed
pad is connected to GND.
Pin Configurations continued at end of data sheet.
________________________________________________________________
Maxim Integrated Products
1
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.
REF
14
8
9
3.0V to 5.5V, 1.25Gbps/2.5Gbps
LAN Laser Drivers
MAX3286–MAX3289/MAX3296–MAX3299
ABSOLUTE MAXIMUM RATINGS
Supply Voltage at V
CC
..........................................-0.5V to +7.0V
Voltage at
EN,
EN, PORDLY, FLTDLY, LV, IN+, IN-,
REF, POL,
POL,
MD, MON, BIASDRV,
MODSET, TC.......................................................-0.5V to (V
CC
+ 0.5V)
Voltage at OUT+, OUT- .........................(V
CC
- 2V) to (V
CC
+ 2V)
Current into FAULT,
FAULT,
POR, SHDNDRV....-1mA to +25mA
Current into OUT+, OUT- ....................................................60mA
Continuous Power Dissipation (T
A
= +70°C)
32-Pin TQFP (derate 14.3mW/°C above +70°C).........1100mW
28-Pin QFN and 28-Pin Thin QFN
(derate 28.7mW/°C above +70°C) ..............................2300mW
16-Pin TSSOP (derate 27mW/°C above +70°C) .........2162mW
Operating Temperature Range...............................0°C to +70°C
Operating Junction Temperature Range ..............0°C to +150°C
Processing Temperature (die) .........................................+400°C
Storage Temperature Range .............................-55°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C
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.
ELECTRICAL CHARACTERISTICS
(V
CC
= +3.0V to +5.5V, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at V
CC
= +3.3V, R
TC
= open and T
A
= +25°C;
see Figure 1a.)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Supply Current
Data Input Voltage Swing
TTL Input Current
TTL Input High Voltage
TTL Input Low Voltage
FAULT,
FAULT
Output High
Voltage
FAULT,
FAULT
Output Low
Voltage
BIAS GENERATOR
(Note 1)
BIASDRV Current, Shutdown
BIASDRV Current Sink
BIASDRV Current Source
REF Voltage
MD Nominal Voltage
MD Voltage During Fault
MD Input Current
MON Input Current
POWER-ON RESET
POR Threshold
POR Hysteresis
FAULT DETECTION
REF Fault Threshold
MD High Fault Threshold
MD Low Fault Threshold
MON Fault Threshold
MODSET, TC Fault Threshold
2
_______________________________________________________________________________________
MAX3286/MAX3288/MAX3296/MAX3298
V
MD
+ 5%
V
MD
- 20%
V
CC
-
600
2.95
V
MD
+ 20%
V
MD
- 5%
V
CC -
480
0.9
V
LV = GND
LV = open
3.9
2.65
150
4.5
3.00
V
mV
V
MD
EN = GND
FAULT = low, V
BIASDRV
≥
0.6V
FAULT = low, V
BIASDRV
≤
V
CC
- 1V
I
REF
≤
2mA, MON = V
CC
APC loop is closed
Common-cathode configuration
Common-anode configuration
Normal operation (FAULT = low)
V
MON
= V
CC
2
-2
-1
0.8
0.8
2.45
1.55
2.65
1.7
0.4
V
CC
- 0.8
+0.16
0.44
+2
6
2.85
1.85
1.2
+1
µA
mA
mA
V
V
V
µA
µA
V
IH
V
IL
V
OH
V
OL
I
OH
= -100µA
I
OL
= 1mA
2.4
0.4
I
CC
V
ID
Figure 1a, R
MOD
= 1.82kΩ
Total differential signal, peak-to-peak, Figure 1a
0
≤
V
PIN
≤
V
CC
200
-100
2
0.8
52
75
1660
+100
mA
mV
µA
V
V
V
V
mV
V
3.0V to 5.5V, 1.25Gbps/2.5Gbps
LAN Laser Drivers
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.0V to +5.5V, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at V
CC
= +3.3V, R
TC
= open and T
A
= +25°C;
see Figure 1a.)
PARAMETER
SHUTDOWN
I
SHDNDRV
= 10µA, FAULT asserted
Voltage at SHDNDRV
LASER MODULATOR
Data Rate
Minimum Laser Modulation
Current
Maximum Laser Modulation
Current
Tolerance of Modulation Current
Modulation-Current Edge
Speed
R
L
≤
25Ω
R
MOD
= 1.9kΩ (I
MOD
= 30mA)
R
MOD
= 13kΩ (I
MOD
= 5mA)
20% to 80%
MAX3286 series
MAX3296 series
R
MOD
= 13kΩ
(I
MOD
= 5mA)
MAX3286 series
R
MOD
= 4.1kΩ
(I
MOD
= 15mA)
R
MOD
= 1.9kΩ
(I
MOD
= 30mA)
R
MOD
= 13kΩ
(I
MOD
= 5mA)
MAX3296 series
R
MOD
= 4.1kΩ
(I
MOD
= 15mA)
R
MOD
= 1.9kΩ
(I
MOD
= 30mA)
Random Jitter (Note 3)
Shutdown Modulation Current
Modulation-Current
Temperature Coefficient
Differential Input Resistance
Output Resistance
Input Bias Voltage
LASER SAFETY CIRCUIT
PORDLY = open
POR Delay
Fault Time
Glitch Rejection at MD
t
PORDLY
t
FAULT
C
PORDLY
= 0.01µF,
MAX3286/MAX3296 only
(Note 4)
10
0.3
3
1.25
5.5
22
20
µs
ms
µs
µs
3
Single ended
Tempco = max, R
MOD
= open; Figure 5
Tempco = min, R
TC
= open; Figure 5
620
42
RMS
MAX3286 series
MAX3296 series
30
-10
-15
130
90
46
29
22
14
8
7
2
2
15
4000
50
800
50
V
CC
- 0.3
980
58
+10
+15
220
150
65
45
35
ps
35
22
20
8
4
200
ps
µA
ppm/°C
Ω
Ω
V
MAX3286 series
MAX3296 series
1.25
2.5
Gbps
I
SHDNDRV
= 15mA, FAULT not asserted
I
SHDNDRV
= 1mA, FAULT not asserted
V
CC
- 0.4
0
0
V
CC
- 1.2
V
CC
- 2.4
V
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
MAX3286–MAX3289/MAX3296–MAX3299
2
mA
mA
%
ps
Deterministic Jitter (Note 2)
_______________________________________________________________________________________
3.0V to 5.5V, 1.25Gbps/2.5Gbps
LAN Laser Drivers
MAX3286–MAX3289/MAX3296–MAX3299
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.0V to +5.5V, T
A
= 0°C to +70°C, unless otherwise noted. Typical values are at V
CC
= +3.3V, R
TC
= open and T
A
= +25°C;
see Figure 1a.)
PARAMETER
FLTDLY Duration
SYMBOL
t
FLTDLY
C
FLTDLY
= 0
C
FLTDLY
= 270pF
MAX3286/MAX3296 only, Figure 1b,
C
FLTDLY
= open
MAX3286/MAX3296 only, Figure 1b,
C
FLTDLY
= 0.01µF
MAX3286/MAX3296 only, Figure 1b
MAX3286/MAX3296 only, Figure 1b
CONDITIONS
MIN
0.2
100
TYP
1
140
6
6
1
3.5
2
5.5
10
MAX
UNITS
µs
ns
µs
µs
µs
EN or
EN
Minimum Pulse Width
t
EN_RESET
Required to Reset a Latched
Fault
FAULT Reset after EN,
EN,
or
POR Transition
SHDNDRV Asserted after EN =
Low or
EN
= High
t
RESET
t
SHUTDN
Note 1:
Common-anode configuration refers to a configuration where POL = GND,
POL
= V
CC
, and an NPN device is used to set
the laser bias current. Common-cathode configuration refers to a configuration where POL = V
CC
,
POL
= GND, and a PNP
device is used to set the laser bias current.
Note 2:
Deterministic jitter measured with a repeating K28.5 bit pattern 00111110101100000101. Deterministic jitter is the peak-to-
peak deviation from the ideal time crossings per ANSI X3.230, Annex A.
Note 3:
For Fibre Channel and Gigabit Ethernet applications, the peak-to-peak random jitter is 14.1 times the RMS jitter.
Note 4:
Delay from a fault on MD until FAULT is asserted high.
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
EYE DIAGRAM
MAX3286 toc02
MAX3286 toc03
POR DELAY vs. C
PORDLY
MAX3286 toc01
FLTDLY DURATION vs. C
FLTDLY
10,000
100,000
10,000
1000
DELAY (µs)
DELAY (µs)
10
100
1000
10,000
100,000
1000
100
100
10
10
1
CAPACITANCE (pF)
1
1
10
100
CAPACITANCE (pF)
1000
10,000
50ps/div
2.5Gbps, 1310nm LASER, 2
7
- 1 PRBS, I
MOD
= 15mA
4
_______________________________________________________________________________________
3.0V to 5.5V, 1.25Gbps/2.5Gbps
LAN Laser Drivers
Typical Operating Characteristics (continued)
(T
A
= +25°C, unless otherwise noted.)
EN STARTUP
(COMMON-ANODE CONFIGURATION)
MAX3286 toc04
MAX3286–MAX3289/MAX3296–MAX3299
MD SHUTDOWN
MAX3286 toc05
EYE DIAGRAM
MAX3286 toc06
EN
MD
FAULT
BIASDRV
FAULT
SHDNDRV
OPTICAL
OUTPUT
5µs/div
OPTICAL
OUTPUT
10µs/div
100ps/div
1.25Gbps, 1310nm LASER, 2
7
- 1 PRBS, I
mod
= 15mA
Pin Description
PIN
QFN/
THIN QFN
MAX3286
MAX3296
1
—
2
3
4, 13, 19
5
TQFP
MAX3286
MAX3296
1
2, 16, 19
3
4
5, 14, 22, 30
6
TSSOP-EP
MAX3287
MAX3297
MAX3289
MAX3299
—
—
—
—
1, 6
—
TSSOP-EP
MAX3288
MAX3298
—
—
—
—
1, 6
—
NAME
FUNCTION
FAULT
N.C.
FAULT
POR
GND
EN
Inverting Fault Indicator. See Table 1.
No Connect
Noninverting Fault Indicator. See Table 1.
Power-On Reset. POR is a TTL-compatible
output. See Figure 14.
Ground
Enable TTL Input. The laser output is enabled
only when EN is high and
EN
is low. If EN is
left unconnected, the laser is disabled.
Inverting Enable TTL Input. The laser output
is enabled only when
EN
is low or grounded
and EN is high. If
EN
is left unconnected, the
laser is disabled.
Power-On Reset Delay. To extend the delay
for the power-on reset circuit, connect a
capacitor to PORDLY. See the
Design
Procedure
section.
6
7
—
—
EN
7
8
—
—
PORDLY
_______________________________________________________________________________________
5
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