19-2281; Rev 4; 11/08
2.7Gbps Laser Driver with Modulation
Compensation
General Description
The MAX3863 is designed for direct modulation of laser
diodes at data rates up to 2.7Gbps. An automatic
power-control (APC) loop is incorporated to maintain a
constant average optical power. Modulation compensa-
tion is available to increase the modulation current in
proportion to the bias current. The optical extinction
ratio is then maintained over temperature and lifetime.
The laser driver can modulate laser diodes at ampli-
tudes up to 80mA. Typical (20% to 80%) edge speeds
are 50ps. The MAX3863 can supply a bias current up
to 100mA. External resistors can set the laser output
levels.
The MAX3863 includes adjustable pulse-width control
to minimize laser pulse-width distortion. The device
offers a failure monitor output to indicate when the APC
loop is unable to maintain the average optical power.
The MAX3863 accepts differential CML clock and data
input signals with on-chip 50Ω termination resistors. If a
clock signal is available, an input data-retiming latch
can be used to reject input pattern-dependent jitter.
The laser driver is fabricated with Maxim’s in-house
second-generation SiGe process.
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Features
Single +3.3V Power Supply
58mA Power-Supply Current
Up to 2.7Gbps (NRZ) Operation
On-Chip Termination Resistors
Automatic Power Control (APC)
Compensation for Constant Extinction Ratio
Programmable Modulation Current Up to 80mA
Programmable Bias Current Up to 100mA
50ps Typical Rise/Fall Time
Pulse-Width Adjustment Circuit
Selectable Data-Retiming Latch
Failure Detector
Mark-Density Monitor
Current Monitors
ESD Protection
MAX3863
Ordering Information
PART
MAX3863ETJ+
MAX3863EGJ
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
32 TQFN-EP*
32 QFN-EP*
+Denotes
a lead-free/RoHS-compliant package.
*EP
= Exposed pad.
Applications
30
BIASMAX
Pin Configuration
28 MODCOMP
32 RTEN
3.2Gbps Data Communications
Add/Drop Multiplexers
Digital Cross-Connects
Section Regenerators
Long-Reach Optical Transmitters
V
CC
27
V
CC
31 EN
WDM Transmission Systems
TOP VIEW
26
BIASMON
29 MODSET
25
MODMON
SONET and SDH Transmission Systems
1
2
3
4
5
6
7
8
*EP
APCFILT1 10
APCFILT2 11
PWC+ 12
PWC- 13
MK+
15
MK-
16
V
CC
14
24
23
22
MDMON
MD
V
CC
DATA+
DATA-
V
CC
V
CC
MAX3863
21
20
19
18
17
MODN
MOD
V
CC
CLK+
CLK-
V
CC
BIAS
FAIL
APCSET
9
Cs
p.
TQFN-EP
QFN-EP
*THE EXPOSED PAD MUST BE SOLDERED TO GND ON THE CIRCUIT BOARD.
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
2.7Gbps Laser Driver with Modulation
Compensation
MAX3863
ABSOLUTE MAXIMUM RATINGS
Supply Voltage V
CC
...............................................-0.5V to +5.0V
DATA+, DATA- and CLK+, CLK- ....(V
CC
- 1.5V) to (V
CC
+ 0.5V)
RTEN, EN,
BIAS, MK+, MK-, PWC+, PWC-
MODMON, BIASMON, MDMON, MODCOMP,
APCFILT1, APCFILT2, BIASMAX, MODSET,
APCSET Voltage ......................................-0.5V to (V
CC
+ 0.5V)
MOD, MODN Voltage .......................................0 to (V
CC
+ 1.5V)
MOD, MODN Current......................................-20mA to +150mA
BIAS Current ...................................................-20mA to +150mA
MD Current............................................................-5mA to +5mA
Operating Junction Temperature Range ...........-55°C to +150°C
Storage Temperature Range .............................-55°C to +150°C
Continuous Power Dissipation (T
A
= +85°C)
32-Pin QFN, TQFN (derate 21.2mW/°C above +85°C) ....1.3W
Processing 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.
ELECTRICAL CHARACTERISTICS
(V
CC
= +3.15V to +3.6V, T
A
= -40°C to +85°C. Typical values are at V
CC
= +3.3V, I
BIAS
= 50mA, I
MOD
= 40mA, T
A
= +25°C, unless
otherwise noted.) (Notes 1, 9)
PARAMETER
Power-Supply Current
Power-Supply Noise Rejection
Power-Supply Threshold
Single-Ended Input Resistance
Bias-Current Setting Range
Bias-Current Setting Error
Bias Off-Current
I
BIAS
to I
BIASMON
Ratio
Bias-Current Temperature Stability
Modulation-Current Setting Range
Modulation-Current Setting Error
Modulation Off-Current
Modulation-Current Temperature
Stability
I
MOD
to I
MODMON
Ratio
Modulation Compensation Range
MD Pin Voltage
Monitor Photodiode Current
Range
APC Loop Time Constant
APC Open Loop
V
MDMON
to I
MD
Ratio
EN
and
RTEN
Input High
EN
and
RTEN
Input Low
FAIL
Output High
FAIL
Output Low
V
IH
V
IL
V
OH
V
OL
Source 150µA
Sink 2mA
2.4
0.4
I
MD
t
APC
(Notes 3, 4)
4mA
≤
I
BIAS
≤
10mA (Note 3)
R
MDMON
= 4kΩ
0.8
2.0
0.8
30
1
4
±390
1.0
1.2
K
K =
ΔI
MODC
/ΔI
BIAS
APC open loop, 25Ω load, T
A
= +25°C
EN
high
APC open loop (Note 3)
-480
38
0
46
APC open loop, 10mA
≤
IBIAS
≤
100mA (Note 3)
APC open loop, 4mA
≤
IBIAS
≤
100mA (Note 3)
7
-15
APC open loop, I
BIAS
= 100mA, T
A
= +25°C
APC open loop, I
BIAS
= 4mA, T
A
= +25°C
EN
high
34
-480
±390
80
+15
0.1
+480
53
1.5
1.75
2000
1000
40
SYMBOL
I
CC
PSNR
(Note 2)
f = 100kHz, 100mV
P-P
(Note 10)
Output enabled
Input to V
CC
40
4
-15
-20
CONDITIONS
MIN
TYP
58
40
2.8
50
60
100
+15
+20
0.1
46
+480
MAX
85
UNITS
mA
dB
V
Ω
mA
%
mA
mA/mA
ppm/°C
mA
%
mA
ppm/°C
mA/mA
mA/mA
V
µA
µs
mA
mV/µA
V
V
V
V
2
_______________________________________________________________________________________
2.7Gbps Laser Driver with Modulation
Compensation
ELECTRICAL CHARACTERISTICS (continued)
(V
CC
= +3.15V to +3.6V, T
A
= -40°C to +85°C. Typical values are at V
CC
= +3.3V, I
BIAS
= 50mA, I
MOD
= 40mA, T
A
= +25°C, unless
otherwise noted.) (Notes 1, 9)
PARAMETER
Single-Ended Input (DC-Coupled)
SYMBOL
V
IS
At high
At low
At high
Single-Ended Input (AC-Coupled)
V
IS
At low
Differential Input Swing
Input Data Rate
Input Return Loss
Turn-Off Delay from
EN
Setup Time
Hold Time
Pulse-Width Adjustment Range
Pulse-Width Stability
Differential Pulse-Width Control
Input Range
Differential Mark Density
Differential Mark-Density Voltage
to Mark-Density Ratio
Output Edge Speed
Output Overshoot
Random Jitter
Deterministic Jitter
t
R
, t
F
δ
Z
L
= 25Ω (20% to 80%) (Notes 3, 6)
Z
L
= 25Ω (Note 3)
(Notes 3, 6)
Data Rate = 2.7Gbps (Notes 3, 8)
Data Rate = 3.2Gbps (Notes 3, 8)
t
SU
t
HD
RL
IN
V
ID
DC-coupled
AC-coupled
NRZ (Note 3)
(Notes 3, 5)
EN
= high (Note 3)
Figure 2 (Note 3)
Figure 2 (Note 3)
Z
L
= 25Ω (Notes 3, 6)
PWC+ and PWC- open (Notes 3, 6)
For PWC+ and PWC- (Notes 3, 7), V
CM
= 0.5V
0% to 100%, V
MK
+ - V
MK
-
15.5
50
±7
0.8
8
10
1.3
40
40
85
-1.0
90
90
±185
±220
±18.5
1.0
±0.85
f
≤
2.7GHz
2.7GHz < f
≤
4GHz
V
CC
- 1.0
V
CC
+
0.05
V
CC
-
0.4
0.2
0.2
3.2
17
14
1.0
CONDITIONS
MIN
TYP
V
CC
V
CC
- 0.1
V
CC
+
0.4
V
V
CC
-
0.05
2.0
1.6
V
P-P
Gbps
dB
µs
ps
ps
ps
ps
V
V
V/%
ps
%
ps
RMS
ps
P-P
MAX
UNITS
V
MAX3863
Specifications at -40°C are guaranteed by design and characterization.
Excluding I
BIAS
, I
MOD
, I
BIASMON
, I
MODMON
, I
FAIL
, and I
PWC
. Input clock and data are AC-coupled.
Guaranteed by design and characterization.
An external capacitor at APCFILT1 and APCFILT2 is used to set the time constant.
For both data inputs DATA+, DATA- and clock inputs CLK+, CLK-.
Measured using a 2.7Gbps repeating 0000 0000 1111 1111 pattern.
For pulse width, PW = 100%: Rp = Rn = 500Ω (or open) or PWC+ = PWC-
≈
+0.5V. For PW > 100%: Rp > Rn or PWC+ >
PWC-. For PW < 100%: Rp < Rn or PWC+ < PWC-.
Note 8:
Measured using a 2
13
- 1 PRBS with 80 zeros + 80 ones input data pattern or equivalent.
Note 9:
AC characterization performed using the circuit in Figure 1.
Note 10:
Power-Supply Noise Rejection (PSNR) = 20log
10
(V
NOISE (on VCC)
/ΔV
OUT
). V
OUT
is the voltage across the 25Ω load when no
input is applied.
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
Note 7:
_______________________________________________________________________________________
3
2.7Gbps Laser Driver with Modulation
Compensation
MAX3863
Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted. See
Typical Operating Circuit.)
ELECTRICAL EYE DIAGRAM
(I
MOD
= 80mA, DATA RATE = 2.7Gbps,
PATTERN 2
13
- 1 + 80CID)
MAX3863 toc01a
ELECTRICAL EYE DIAGRAM
(I
MOD
= 80mA, DATA RATE = 3.2Gbps,
PATTERN 2
13
- 1 + 80CID)
MAX3863 toc01b
ELECTRICAL EYE DIAGRAM
(I
MOD
= 7mA, DATA RATE = 2.7Gbps,
PATTERN 2
13
- 1 + 80CID)
MAX3863 toc02a
52ps/div
52ps/div
52ps/div
ELECTRICAL EYE DIAGRAM
(I
MOD
= 7mA, DATA RATE = 3.2Gbps,
PATTERN 2
13
- 1 + 80CID)
MAX3863 toc02b
OPTICAL EYE DIAGRAM
(I
MOD
= 40mA, DATA RATE = 2.5Gbps,
PATTERN 2
13
- 1 + 80CID)
MAX3863 toc03a
OPTICAL EYE DIAGRAM
(I
MOD
= 40mA, DATA RATE = 3.2Gbps,
PATTERN 2
13
- 1 + 80CID)
MAX3863 toc03b
52ps/div
58ps/div
58ps/div
SUPPLY CURRENT (I
CC
) vs.TEMPERATURE
(EXCLUDES BIAS AND
MODULATION CURRENTS)
MAX3863 toc04
DETERMINISTIC JITTER vs. I
MOD
MAX3863 toc05
PULSE-WIDTH ADJUST
vs. DIFFERENTIAL V
PWC
MAX3863 toc06
80
75
SUPPLY CURRENT (mA)
70
65
60
55
50
45
40
-40
-20
0
20
40
60
16
14
DETERMINISTIC JITTER (ps
P-P
)
12
3.2Gbps
10
8
6
4
2
0
5
15
25
35
45
55
65
75
2.7Gbps
300
200
PULSE-WIDTH ADJUST (ps)
100
0
-100
-200
-300
80
85
-0.8 -0.6 -0.4 -0.2
0
0.2
0.4
0.6
0.8
TEMPERATURE (°C)
I
MOD
(mA)
V
PWC+
- V
PWC-
(V)
4
_______________________________________________________________________________________
2.7Gbps Laser Driver with Modulation
Compensation
Typical Operating Characteristics (continued)
(T
A
= +25°C, unless otherwise noted. See
Typical Operating Circuit.)
MODULATION CURRENT vs.
MODULATION SET RESISTOR
MAX3863 toc07
MAX3863
MODULATION MONITOR VOLTAGE
vs. MODULATION CURRENT
180
160
140
V
MODMON
(mV)
MAX3863 toc08
BIAS CURRENT
vs. BIASMAX SET RESISTOR
MAX3863 toc09
100
200
1000
100
I
BIAS
(mA)
10
1
5
20
35
50
65
80
0.1
1
10
R
BIASMAX
(kΩ)
100
I
MOD
(mA)
I
MOD
(mA)
120
100
80
60
40
20
10
1
0.1
1
R
MODSET
(kΩ)
10
100
0
BIAS MONITOR VOLTAGE
vs. BIAS CURRENT
MAX3863toc10
MONITOR DIODE CURRENT
vs. APCSET RESISTOR
MAX3863 toc11
DIODE-CURRENT MONITOR VOLTAGE
vs. MONITOR DIODE CURRENT
MAX3863 toc12
300
250
V
BIASMON
(mV)
200
10
3.0
2.5
2.0
1.5
1.0
0.5
150
100
50
0
0
10 20 30 40 50 60 70 80 90 100
I
BIAS
(mA)
0.1
0.01
0.1
1
10
R
APCSET
(kΩ)
100
1000
V
MDMON
(V)
1
I
BIAS
(mA)
0
0
0.5
1.0
1.5
2.0
2.5
I
MD
(mA)
COMPENSATION (K)
vs. R
MODCOMP
MAX3863 toc13
POWER-SUPPLY NOISE REJECTION
vs. FREQUENCY
MAX3863 toc14
SINGLE-ENDED S11 vs. FREQUENCY
-5
MAGNITUDE S11 (dB)
-10
-15
-20
-25
-30
MAX3863 toc15
10
120
100
80
PSNR (dB)
60
40
20
0
1
K (mA/mA)
0.1
-35
-40
0.1
1
10
100
1000
10,000
0
1
2
3
4
5
FREQUENCY (kHz)
FREQUENCY (GHz)
0.01
0.01
0.1
1
R
MODCOMP
(kΩ)
10
100
0
_______________________________________________________________________________________
5