19-2081; Rev 3; 2/07
+3.3V, 2.5Gbps Low-Power Laser Driver
General Description
The MAX3273 is a compact, low-power laser driver for
applications up to 2.7Gbps. The device uses a single
+3.3V supply and typically consumes 30mA. The bias
and modulation current levels are programmed by
external resistors. An automatic power-control (APC)
loop is incorporated to maintain a constant average
optical power over temperature and lifetime. The laser
driver is fabricated using Maxim’s in-house, second-
generation SiGe process.
The MAX3273 accepts differential CML-compatible
clock and data input signals. Inputs are self-biased to
allow AC-coupling. An input data-retiming latch can be
enabled to reject input jitter if a clock signal is available.
The driver can provide bias current up to 100mA and
modulation current up to 60mA
P-P
with typical (20% to
80%) edge speeds of 59ps. A failure-monitor output is
provided to indicate when the APC loop is unable to
maintain average optical power. The MAX3273 is avail-
able in 4mm
✕
4mm, 24-pin QFN and thin QFN pack-
ages, as well as in die form.
♦
30mA Power-Supply Current
♦
Single +3.3V Power Supply
♦
Up to 2.7Gbps (NRZ) Operation
♦
Automatic Average Power Control with Failure
Monitor
♦
Programmable Modulation Current from 5mA to
60mA
♦
Programmable Bias Current from 1mA to 100mA
♦
Typical Fall Time of 59ps
♦
Selectable Data Retiming Latch
♦
Complies with ANSI, ITU, and Bellcore
SDH/SONET Specifications
Features
MAX3273
Ordering Information
PART
MAX3273EGG
TEMP RANGE
-40°C to +85°C
PIN-
PACKAGE
24 QFN
(4mm 4mm)
24 Thin QFN
(4mm 4mm)
PACKAGE
CODE
G2444-1
T2444-2
—
Applications
SONET OC-48 and SDH STM-16
Transmission Systems
Add/Drop Multiplexers
Digital Cross-Connects
2.5Gbps Optical Transmitters
Pin Configurations appear at end of data sheet.
MAX3273ETG+ -40°C to +85°C
MAX3273E/D
-40°C to +85°C Dice*
*Dice
are designed to operate from T
A
= -40°C to +85°C, but
are tested and guaranteed at T
A
= +25°C only.
+Denotes
lead-free package.
Typical Application Circuit
V
CC
0.01μF
V
CC
APCFILT1
V
CC
APCFILT2
LATCH
25Ω
OUT-
L
P2
DATA -
OUT+
25Ω
0.056μF
20Ω
L
P1
L
P1
DATA +
50Ω
100Ω
DATA +
DATA -
2.5Gbps
SERIALIZER
WITH CLOCK
GENERATION
CLK+
50Ω
MAX3273
50Ω
100Ω
MODSET
BIASMAX
APCSET
GND
CLK+
BIAS
FAIL
EN
CLK-
50Ω
CLK-
MD
500pF
REPRESENTS A CONTROLLED-IMPEDANCE TRANSMISSION LINE.
†
.
________________________________________________________________
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.
+3.3V, 2.5Gbps Low-Power Laser Driver
MAX3273
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V
CC
..............................................-0.5V to +6.0V
Current into BIAS, OUT+, OUT- ......................-20mA to +150mA
Current into MD.....................................................-5mA to +5mA
Voltage at DATA+, DATA-, CLK+,
CLK-, LATCH,
EN, FAIL..........................-0.5V
to (V
CC
+ 0.5V)
Voltage at MODSET, BIASMAX,
APCSET, APCFILT1, APCFILT2.........................-0.5V to +3.0V
Voltage at BIAS .........................................+1.0V to (V
CC
+ 1.5V)
Voltage at OUT+, OUT-.............................+1.5V to (V
CC
+ 1.5V)
Current into
FAIL
...............................................-10mA to +10mA
Continuous Power Dissipation (T
A
= +85°C)
24-Pin QFN (derate 274mW/°C above +85°C) ..........1781mW
Storage Temperature Range .............................-55°C to +150°C
Operating Junction Temperature ......................-55°C to +150°C
Die Attach Temperature (die) ..........................................+400°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.
DC ELECTRICAL CHARACTERISTICS
(V
CC
= +3.14V to +3.6V, T
A
= -40°C to +85°C. Typical values are at V
CC
= +3.3V, I
BIAS
= 60mA, I
MOD
= 30mA, T
A
= +25°C, unless
otherwise noted.) (Note 1)
PARAMETER
Supply Current
Bias-Current Range
Bias Off-Current
Bias-Current Stability
Bias-Current Absolute Accuracy
Differential Input Voltage
Common-Mode Input Voltage
TTL Input High Voltage
TTL Input Low Voltage
TTL Output High
TTL Output Low
MD Voltage
Monitor Diode DC-Current Range
Monitor-Diode Bias Set Point
Stability
Monitor-Diode Bias Absolute
Accuracy
I
MD
(Note 3)
I
MD
= 1000µA
I
MD
= 18µA
18
-480
-480
-15
83
159
V
ID
V
ICM
V
IH
V
IL
V
OH
V
OL
Sourcing 50µA
Sinking 100µA
2.4
0.4
1.6
1000
+480
+480
+15
SYMBOL
I
CC
I
BIAS
CONDITIONS
Excluding I
BIAS
and I
MOD
Voltage on BIAS pin (V
BIAS
) = V
CC
- 1.6V
EN
= high (Note 2), V
BIAS
≤
2.6V
APC open loop (Note 3)
APC open loop (Note 4)
Figure 1
I
BIAS
= 100mA
I
BIAS
= 1mA
-15
0.2
V
CC
-
1.49
2.0
0.8
V
CC
-
1.32
61
198
+15
1.6
V
CC
-
V
ID
/4
1
MIN
TYP
30
MAX
45
100
0.2
UNITS
mA
mA
mA
ppm/°C
%
V
P-P
V
V
V
V
V
V
µA
ppm/°C
%
2
_______________________________________________________________________________________
+3.3V, 2.5Gbps Low-Power Laser Driver
AC ELECTRICAL CHARACTERISTICS
(V
CC
= +3.14V to +3.6V, T
A
= -40°C to +85°C. Typical values are at V
CC
= +3.3V, I
BIAS
= 60mA, I
MOD
= 30mA, T
A
= +25°C, unless
otherwise noted.) (Notes 5, 6)
PARAMETER
Modulation-Current Range
Modulation Off-Current
Modulation-Current Stability
Modulation-Current Absolute
Accuracy
Output Current Rise Time
Output Current Fall Time
Output Overshoot/Undershoot
Enable and Startup Delay
Maximum Consecutive Identical
Digits
Pulse-Width Distortion
Random Jitter
Input Latch Setup Time
Input Latch Hold Time
T
SU
T
HD
LATCH = high (Figure 1)
LATCH = high (Figure 1)
PWD
(Notes 7, 8)
t
R
t
F
δ
SYMBOL
I
MOD
(Note 3)
EN
= high
I
MOD
= 60mA
I
MOD
= 5mA
(Note 4)
20% to 80% (Note 7)
20% to 80% (Note 7)
(Note 7)
APC open loop
80
3
1.0
75
0
45
1.5
150
50
-480
-480
-15
52
59
15
364
64
34
CONDITIONS
MIN
5
TYP
MAX
60
0.2
+480
+480
+15
87
104
UNITS
mA
mA
ppm/°C
%
ps
ps
%
ns
bits
ps
ps
RMS
ps
ps
MAX3273
Specifications at -40°C are guaranteed by design and characterization. Dice are tested at T
A
= +25°C only.
Both the bias and modulation currents are switched off if any of the current set pins is grounded.
Guaranteed by design and characterization.
Accuracy refers to part-to-part variation.
AC characterization was performed by using the circuit in Figure 2.
AC characteristics are guaranteed by design and characterization, and measured using a 2.5Gbps 2
13
- 1 PRBS input data
pattern with 80 consecutive zeros and 80 consecutive ones added.
Note 7:
Measured using a 2.5Gbps repeating 0000 1111 pattern.
Note 8:
PWD = (wide pulse - narrow pulse) / 2.
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
_______________________________________________________________________________________
3
+3.3V, 2.5Gbps Low-Power Laser Driver
MAX3273
CLK+
V
IS
= 0.1V TO 0.8V
CLK-
T
SU
DATA-
V
IS
= 0.1V TO 0.8V
DATA+
T
HD
V
ID
= 0.2V TO 1.6V
(DATA+) - (DATA-)
5mA TO 60mA
I
MOD
Figure 1. Required Input Signal and Setup/Hold-Time Definition
V
CC
L
P1
= MURATA BLM11HA601SPT
L
P2
= MURATA BLM21HA102SPT
L
P3
= COILCRAFT D01607C-333
L
P3
L
P2
L
P2
L
P1
MAX3273
OUT-
L
P1
25Ω
OSCILLOSCOPE
0.056μF
50Ω
0.056μF
V
CC
50Ω
50Ω
OUT+
BIAS
15Ω
Figure 2. Output Termination for Characterization
4
_______________________________________________________________________________________
+3.3V, 2.5Gbps Low-Power Laser Driver
Typical Operating Characteristics
(V
CC
= 3.3V, T
A
= +25°C, unless otherwise noted.)
ELECTRICAL EYE DIAGRAM
(I
MOD
= 20mA, 2
13
- 1 80CID)
MAX3273 toc01
MAX3273
ELECTRICAL EYE DIAGRAM
(I
MOD
= 60mA, 2
13
- 1 80CID)
MAX3273 toc02
400mV/div
125mV/div
60ps/div
60ps/div
OPTICAL EYE DIAGRAM
(2.488Gbps, 1300nm FP LASER,
1.87GHz FILTER)
MAX3273 toc03
I
BIASMAX
vs. R
BIASMAX
MAX3273 toc04
I
MOD
vs. R
MODSET
80
70
60
I
MOD
(mA)
50
40
30
20
MAX3273 toc05
140
120
100
I
BIASMAX
(mA)
80
60
40
20
0
90
10
0
0.1
1
10
R
BIASMAX
(kΩ)
100
1000
0.1
1
10
R
MODSET
(kΩ)
100
57ps/div
MITSUBISHI ML725C8F
LASER DIODE
I
MD
vs. R
APCSET
MAX3273 toc06
SUPPLY CURRENT vs. TEMPERATURE
90
80
SUPPLY CURRENT (mA)
70
60
50
40
30
20
EXCLUDE I
BIAS
, I
MOD
25Ω LOAD
MAX3273 toc07
1.4
1.2
1.0
I
MD
(mA)
0.8
0.6
0.4
0.2
0
0.1
1
R
APCSET
(kΩ)
10
100
10
0
100
-40
-15
10
35
60
85
TEMPERATURE (°C)
_______________________________________________________________________________________
5