19-1570; Rev 4; 1/05
KIT
ATION
EVALU
BLE
AVAILA
+3.3V, 2.5Gbps SDH/SONET Laser Driver
with Current Monitors and APC
General Description
Features
♦
Single +3.3V or +5V Power Supply
♦
64mA Supply Current at +3.3V
♦
Programmable Bias Current from 1mA to 100mA
♦
Programmable Modulation Current from
5mA to 60mA
♦
Bias Current and Modulation Current Monitors
♦
87ps Rise/Fall Time
♦
Automatic Average Power Control with Failure
Monitor
♦
Complies with ANSI, ITU, and Bellcore
SDH/SONET Specifications
♦
Enable Control
MAX3869
The MAX3869 is a complete, single +3.3V laser driver
for SDH/SONET applications up to 2.5Gbps. The
device accepts differential PECL data and clock inputs
and provides bias and modulation currents for driving a
laser. A synchronizing input latch can be used (if a
clock signal is available) to reduce jitter.
An automatic power control (APC) feedback loop is
incorporated to maintain a constant average optical
power over temperature and lifetime. The wide modula-
tion current range of 5mA to 60mA and bias current of
1mA to 100mA are easy to program, making this prod-
uct ideal for use in various SDH/SONET applications.
The MAX3869 also provides enable control, two current
monitors that are directly proportional to the laser bias and
modulation currents, and a failure-monitor output to indi-
cate when the APC loop is unable to maintain the average
optical power. The MAX3869 is available in 32-pin TQFP
and small 32-pin QFN packages as well as dice.
Ordering Information
PART
TEMP RANGE
-40°C to +85°C
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
32 TQFP-EP*
32 TQFP-EP*
32 QFN**
MAX3869EHJ
MAX3869EHJ+
MAX3869EGJ
Applications
SONET/SDH Transmission Systems
Add/Drop Multiplexers
Digital Cross-Connects
Section Regenerators
2.5Gbps Optical Transmitters
Pin Configuration appears at end of data sheet.
MAX3869E/D
-40°C to +85°C
Dice***
*Exposed
pad.
**Package
Code: G3255-1
***Dice
are designed to operate over this range, but are tested and
guaranteed at T
A
= +25°C only. Contact factory for availability.
+Denotes
lead-free package.
Typical Application Circuit
+3.3V
ENABLE
LATCH
+3.3V
FAIL
0.01µF
LD
FERRITE
BEAD
23Ω
0.056µF
SERIALIZER
WITH
CLOCK GEN.
84.5Ω
84.5Ω
84.5Ω
84.5Ω
CLK+
CLK-
MD
BIASMAX
MODSET
APCFILT
APCSET
BIASMON
CAPC
MODMON
1000pF
MAX3869
BIAS
124Ω
124Ω
124Ω
124Ω
DATA+
25Ω
OUT-
OUT+
MAX3890
DATA-
+3.3V
________________________________________________________________
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 SDH/SONET Laser Driver
with Current Monitors and APC
MAX3869
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, V
CC
............................................. -0.5V to +7.0V
Current into BIAS ...........................................-20mA to +150mA
Current into OUT+, OUT- ................................-20mA to +100mA
Current into MD.....................................................-5mA to +5mA
Voltage at DATA+, DATA-, CLK+, CLK-, ENABLE,
LATCH,
FAIL,
BIASMON, MODMON .....-0.5V to (V
CC
+ 0.5V)
Voltage at APCFILT, CAPC, MODSET,
BIASMAX, APCSET ...........................................-0.5V to +3.0V
Voltage at OUT+, OUT-.............................+1.5V to (V
CC
+ 1.5V)
Voltage at BIAS .........................................+1.0V to (V
CC
+ 0.5V)
Continuous Power Dissipation (T
A
= +85°C)
32-Pin TQFP-EP (derate 22.2mW/°C above +85°C) ..1444mW
32-Pin QFN (derate 20.84mW/°C above +85°C) .......1667mW
Storage Temperature Range .............................-65°C to +165°C
Operating Junction Temperature Range ...........-55°C to +150°C
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.
DC ELECTRICAL CHARACTERISTICS
(V
CC
= +3.14V to +5.5V, T
A
= -40°C to +85°C. Typical values are at V
CC
= +3.3V, I
MOD
= 30mA, I
BIAS
= 60mA, 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
Clock and Data Input Current
TTL Input High Voltage
TTL Input Low Voltage
TTL Output High Voltage
FAIL
TTL Output Low Voltage
FAIL
Monitor-Diode Reverse Bias
Voltage
Monitor-Diode DC Current Range
Monitor-Diode Bias Setpoint
Stability
Monitor-Diode Bias Absolute
Accuracy
BIASMON to I
BIAS
Gain
MODMON to I
MOD
Gain
A
BIAS
A
MOD
I
MD
(Note 6)
(Note 5)
I
BIAS
/I
BIASMON
I
MOD
/I
MODMON
I
MD
= 1mA
I
MD
= 18µA
-15
37
29
(Note 5)
V
ID
V
ICM
I
IN
ENABLE, LATCH
ENABLE, LATCH
Sourcing 50µA
Sinking 100µA
2.4
0.1
1.5
18
-480
50
90
15
1000
480
V
CC
- 0.3
SYMBOL
I
CC
I
BIAS
I
BIAS-OFF
(Note 2)
(Note 3)
ENABLE = low (Note 4)
APC open loop
APC open loop
Figure 1
PECL compatible
I
BIAS
= 100mA
I
BIAS
= 1mA
-15
200
V
CC
-
1.49
-1
2.0
0.8
V
CC
0.44
V
CC
-
1.32
230
900
15
1600
V
CC
-
V
ID
/4
10
1
CONDITIONS
MIN
TYP
64
MAX
112
100
100
UNITS
mA
mA
µA
ppm/°C
%
mVp-p
V
µA
V
V
V
V
V
µA
ppm/°C
%
A/A
A/A
2
_______________________________________________________________________________________
+3.3V, 2.5Gbps SDH/SONET Laser Driver
with Current Monitors and APC
AC ELECTRICAL CHARACTERISTICS
(V
CC
= +3.14V to +5.5V, load as shown in Figure 2, T
A
= -40°C to +85°C. Typical values are at V
CC
= +3.3V, I
MOD
= 30mA, T
A
= +25°C.)
(Note 7)
PARAMETER
Input Latch Setup Time
Input Latch Hold Time
Modulation-Current Range
Modulation-Off Current
Modulation-Current Stability
Modulation-Current Absolute
Accuracy
Output Rise-Time
Output Fall- Time
Output Aberrations
Enable and Start-Up Delay
Maximum Consecutive Identical
Digits
Pulse-Width Distortion
Jitter Generation
Note 1:
Note 2:
Note 3:
Note 4:
Note 5:
Note 6:
PWD
(Notes 8, 9)
Jitter BW = 12kHz to 20MHz, 0-1 pattern
80
14
7
50
20
t
R
t
F
SYMBOL
t
SU
t
H
I
MOD
I
MOD-OFF
ENABLE = low (Note 4)
I
MOD
= 60mA
I
MOD
= 5mA
(Note 5)
20% to 80% (Note 8)
20% to 80% (Note 8)
(Note 8)
MAX3869EHJ
MAX3869E/D
MAX3869EHJ
MAX3869E/D
-15
78
69
87
79
±15
250
(Note 10)
-480
-8
300
15
CONDITIONS
LATCH = high, Figure 3
LATCH = high, Figure 3
MIN
100
100
5
60
200
480
TYP
MAX
UNITS
ps
ps
mA
µA
ppm/°C
%
ps
ps
%
ns
bits
ps
ps
p-p
MAX3869
Dice are tested at T
A
= +25°C only.
Tested at R
MODSET
= 2.49kΩ, R
BIASMAX
= 1.69kΩ, excluding I
BIAS
and I
MOD
.
Voltage on BIAS pin is (V
CC
- 1.6V).
Both the bias and modulation currents will be switched off if any of the current set pins are grounded.
Accuracy refers to part-to-part variation.
Assuming that the laser to monitor-diode transfer function does not change with temperature. Guaranteed by design and
characterization.
Note 7:
AC characteristics are guaranteed by design and characterization.
Note 8:
Measured with 622Mbps 0-1 pattern, LATCH = high.
Note 9:
PWD = (wider pulse - narrower pulse) / 2.
Note 10:
See
Typical Operating Characteristics
for worst-case distribution.
DATA+
DATA-
100mV MIN
800mV MAX
200mVp-p MIN
(DATA+) - (DATA-)
1600mVp-p MAX
I
OUT
+
I
MOD
Figure 1. Required Input Signal and Output Polarity
_______________________________________________________________________________________
3
+3.3V, 2.5Gbps SDH/SONET Laser Driver
with Current Monitors and APC
MAX3869
V
CC
t
CLK
= 402ps
A
A
A, B ARE SMD FERRITE BEADS:
B = BLM11A601S MURATA ELECTRONICS
A = BLM21A102S MURATA ELECTRONICS
CLK
t
SU
t
H
B
B
0.056µF
25Ω
DATA
MAX3869
OUT-
I
OUT+
OUT+
0.056µF
BIAS
15Ω
50Ω
50Ω
OSCILLOSCOPE
Figure 3. Setup/Hold Time Definition
V
CC
Figure 2. Output Termination for Characterization
Typical Operating Characteristics
(V
CC
= +3.3V, load as shown in Figure 2, T
A
= +25°C, unless otherwise noted.)
EYE DIAGRAM
(2.488Gbps, 1300nm FP LASER,
1.87GHz FILTER, 32 TQFP-EP)
MAX3869-01
TYPICAL DISTRIBUTION OF FALL TIME
MAX3869-02
DISTRIBUTION OF FALL TIME
(WORST-CASE CONDITIONS)
32 TQFP-EP
I
MOD
= 60mA
V
CC
= 3.14V
T
A
= +85°C
MAX3869-03
25
32 TQFP-EP
I
MOD
= 30mA
20
PERCENT OF UNITS (%)
35
30
PERCENT OF UNITS (%)
25
20
15
10
5
MEAN = 119.1ps
σ
= 2.0ps
15
MEAN = 87.3ps
σ
= 1.6ps
10
5
0
48ps/div
MITSUBISHI ML725C8F LASER DIODE
83
84
85
86 87 88 89
FALL TIME (ps)
90
91
92
0
113 114.5 116 117.5 119 120.5 122 123.5 125 126.5
FALL TIME (ps)
4
_______________________________________________________________________________________
+3.3V, 2.5Gbps SDH/SONET Laser Driver
with Current Monitors and APC
MAX3869
Typical Operating Characteristics (continued)
(V
CC
= +3.3V, load as shown in Figure 2, T
A
= +25°C, unless otherwise noted.)
ELECTRICAL EYE DIAGRAM
(I
MOD
= 30mA, 2
13
-1 +80 CID, 32 TQFP-EP)
MAX3869-04
ELECTRICAL EYE DIAGRAM
(I
MOD
= 60mA, 2
13
-1 +80 CID, 32 TQFP-EP)
MAX3869-05
RANDOM JITTER vs. I
MOD
7.5
7.0
RANDOM JITTER (psp-p)
6.5
6.0
5.5
5.0
4.5
4.0
3.5
3.0
5
10
15
20
25
30
35
40
45
50
MAX3869-06
8.0
250mV/div
100ps/div
400mV/div
100ps/div
I
MOD
(mA)
I
BIASMAX
vs. R
BIASMAX
MAX3869-07
I
MOD
vs. R
MODSET
MAX3869-08
I
MD
vs. R
APCSET
1.1
1.0
0.9
I
MD
(mA)
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
MAX3869-09
120
100
80
60
40
20
0
1
10
R
BIASMAX
(kΩ)
100
100
90
80
70
I
MOD
(mA)
60
50
40
30
20
10
0
1.2
I
BIASMAX
(mA)
300
1
10
R
MODSET
(kΩ)
100
0.1
1
R
APCSET
(kΩ)
10
100
SUPPLY CURRENT vs. TEMPERATURE
(EXCLUDE I
BIAS
, I
MOD
, 25Ω LOAD)
MAX3869-10
BIAS-CURRENT MONITOR GAIN
vs. TEMPERATURE
MAX3869-11
100
90
80
SUPPLY CURRENT (mA)
70
60
50
40
30
20
10
0
-40
-15
10
35
60
V
CC
= +3.14V
V
CC
= +5.5V
50
I
BIAS
= 100mA, I
MOD
= 50mA
I
BIAS
= 10mA, I
MOD
= 10mA
30
40
GAIN (I
BIAS
/I
BIASMON
)
85
20
10
0
-40
-15
10
35
60
85
TEMPERATURE (°C)
TEMPERATURE (°C)
_______________________________________________________________________________________
5
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