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MAX3740A - MAX3740A
MAX3740A
MAX3740A available compact 4mm, 24-pin thin package operates over -40°C +85°C temperature range.
MAX3740A operates 3.2Gbps. switch 15mA laser modulation current source 15mA bias current. Adjustable temperature compensation provided keep optical extinction ratio within specifications over operating temperature range. MAX3740A interfaces with Dallas DS1858 meet SFF-8472 timing diagnostic requirements. MAX3740A accommodates various VCSEL packages, including low-cost TO-46 headers. MAX3740A safety circuit detects faults that could cause hazardous light levels disables VCSEL output. safety circuits compliant with multisource agreements (MSA).
MAX3740A high-speed VCSEL driver smallform-factor (SFF) small-form-factor pluggable (SFP) fiber optic transmitters. contains bias generator, laser modulator, comprehensive safety features. automatic power control (APC) adjusts laser bias current maintain average optical power over changes temperature laser properties. driver accommodates common cathode differential configurations.
pricing, delivery, ordering information, please contact Maxim/Dallas Direct! 1-888-629-4642, visit Maxim's website www.maxim-ic.com.
19-3118; 6/04
Infiniband Optical Transmitters
Fibre Channel Optical Transmitters
Gigabit Ethernet Optical Transmitters
Multirate (1Gbps 3.2Gbps) SFP/SFF Modules
3.2Gbps VCSEL Driver with Diagnostic Monitors
Maxim Integrated Products
General Description
Applications
24-Pin Thin Package
Safety Circuits Compliant with MSAs
Automatic Power Control
Supports Common Cathode Differential Configuration
Optional Peaking Current Improve VCSEL Edge Speed
15mA Bias Current
15mA Modulation Current
Supports SFF-8472 Digital Diagnostics
+Denotes lead-free package.
MAX3740AETG
MAX3740AETG+
RBIASSET
PART
OPTIONAL COMPONENT
*FERRITE BEAD
0.1µF
0.1µF
SQUELCH
TX_DISABLE
BIASSET
PEAKSET
Typical Application Circuit
MAX3740A
-40°C +85°C Thin (4mm 4mm)
-40°C +85°C Thin (4mm 4mm)
TEMP RANGE PIN-PACKAGE
RPEAKSET
+3.3V
Ordering Information
BIASMON
FAULT PWRMON MODSET
COMP
OUT+
OUT-
BIAS
RBIASMON
0.01µF
0.01µF
0.047µF
4.7k
RMODSET
Features
RPWRSET
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MAX3740A
Supply Voltage (VCC) .-0.5V 6.0V Voltage TX_DISABLE, IN+, IN-, FAULT, SQUELCH TC1, TC2, MODSET, PEAKSET, BIASSET, BIAS, BIASMON, COMP, REF, PWRMON .-0.5V (VCC 0.5V) Voltage OUT+, OUT- .(VCC (VCC Current into FAULT -1mA +25mA Current into OUT+, OUT- .60mA
ABSOLUTE MAXIMUM RATINGS
(VCC +2.97V +3.63V, -40°C +85°C. Typical values +3.3V, shorted, PEAKSET open, +25°C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS
3.2Gbps VCSEL Driver with Diagnostic Monitors
Stresses beyond those listed under "Absolute Maximum Ratings" cause permanent damage device. These stress ratings only, functional operation device these other conditions beyond those indicated operational sections specifications implied. Exposure absolute maximum rating conditions extended periods affect device reliability.
Accuracy Programmed Bias Current
Bias Current
BIAS GENERATOR (Note
Time Resume from Squelch
Time Squelch Data
Squelch Hysteresis
Squelch Threshold
SQUELCH
Power-Down Time
Input Voltage
Input High Voltage
Input Impedance
TX_DISABLE INPUT
Output Voltage
Output High Voltage
FAULT OUTPUT
Supply Current
PARAMETER SYMBOL ICC-SHDN BIAS IBIAS (Note (Note time reach ICC-SHDN when TX_DISABLE transitions high IBIAS IBIAS 15mA Maximum Minimum RLOAD 4.7k 3.63V RLOAD 2.97V Total current when TX_DISABLE high Additional current when SQUELCH high Additional current when peaking used (Note SQUELCH low, IMOD 2mAP-P TX_DISABLE low, peaking used IMOD 15mAP-P (Note CONDITIONS 0.02 0.02
Continuous Power Dissipation +85°C) 24-Lead Thin (derate 20.8mW/°C above +85°C).1354mW Operating Temperature Range .-40°C +85°C Storage Temperature Range .-55°C +150°C Lead Temperature (soldering, 10s) .+300°C
10.0
5.00
5.00
UNITS
mVP-P
mVP-P
MAX3740A
(VCC +2.97V +3.63V, -40°C +85°C. Typical values +3.3V, shorted, PEAKSET open, +25°C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS (continued)
Input Bias Voltage
Input Resistance
Laser Modulation During Fault while Squelch Active
Random Jitter
Deterministic Jitter
Modulation Transition Time
Maximum Programmable Temperature Coefficient
Minimum Programmable Temperature Coefficient
Tolerance Programmed Modulation Current
Peaking Current Duration
Maximum Peaking Current Range
Minimum Peaking Current Range
Modulation Current
Output Resistance
Data Input Voltage Swing
LASER MODULATOR (Note
PWRMON Nominal Gain
Time Constant
Input Current
Voltage During Fault
Voltage
Nominal Voltage
AUTOMATIC POWER CONTROL (APC)
BIASMON Stability
BIASMON Gain
Bias Current During Fault
PARAMETER
3.2Gbps VCSEL Driver with Diagnostic Monitors
IMOD_OFF SYMBOL IBIAS_OFF IMOD VREF Temperature range +70°C shorted Single-ended resistance OUT3mA IBIAS 15mA IMOD 15mA, 3.2Gbps (Notes IMOD 15mA, (Note Maximum Minimum Single-ended resistance OUT+ Maximum Minimum loop closed IBIAS Current BIAS CCOMP 0.047µF (Note (Note Normal operation (FAULT low) Differential resistance (Notes 5,6) VPWRMON (VREF VMD) CONDITIONS 0.0875 0.085 2200 1.85 +5000 VREF 0.105 0.105 2.15 0.1375 0.125 2.45 µAP-P psP-P
ppm/°C
ppm/°C
mA/mA
UNITS
psRMS
mAP-P
mVP-P
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MAX3740A
(VCC +2.97V +3.63V, -40°C +85°C. Typical values +3.3V, shorted, PEAKSET open, +25°C, unless otherwise noted.)
ELECTRICAL CHARACTERISTICS (continued)
3.2Gbps VCSEL Driver with Diagnostic Monitors
Note Supply current measurements exclude IBIAS from total current. Note Tested with RPEAK 1.18k. Note Measured applying pattern that contains 20µs K28.5, followed zeros, then 20µs K28.5, followed ones. Data rate equal 2.5Gbps, with inputs filtered using 1.8GHz Bessel filters. Note VBIAS 0.7V. Note Variation bias monitor gain single part over range VCC, temperature, IBIAS 15mA. Note Guaranteed design characterization. Note Measured electrically with load AC-coupled OUT+. Note Deterministic jitter peak-to-peak deviation from ideal time crossings measured with K28.5 pattern 3.2Gbps
TX_DISABLE Reset
Fault Delay Time
Fault Assert Time
Power-On Time
Fault Reset Time
Disable Negate Time
Disable Time
Power-Monitor Fault Threshold
VBIAS Fault Threshold
High-Current Fault Threshold
SAFETY FEATURES (see Typical Operating Characteristics section)
PARAMETER SYMBOL t_FLTDLY t_FAULT VBMTH VPMTH t_INIT2 t_INIT1 t_OFF VBTH t_ON t_RESET Time from fault occurrence VFAULT high; CFAULT 20pF, RFAULT 4.7k (Note Time after power-on transmitter-on with TX_DISABLE (Note Time VFAULT after power-on after rising edge TX_DISABLE (Note Time TX_DISABLE must held high reset FAULT (Note Time from fault IBIAS IBIAS_OFF IMOD IMOD_OFF (Note Time from rising edge TX_DISABLE IBIAS IMOD steady state (Note Time from rising edge TX_DISABLE IBIAS IBIAS_OFF IMOD IMOD_OFF (Note VPWRMON VPMTH causes fault VBIAS referenced VBIASMON VBMTH causes fault CONDITIONS -0.250 -0.2
-0.150
UNITS
DETERMINISTIC JITTER (psP-P)
MAX3740A
73mV/div
(VCC +3.3V, PEAKSET open, measured electrically with load AC-coupled OUT+, +25°C, unless otherwise noted.)
RANDOM JITTER (psRMS)
TRANSITION TIME (ps)
MAX3740A toc08
MAX3740A toc07
DETERMINISTIC JITTER MODULATION CURRENT
EMCORE SC-TOSA-8585-3420 VCSEL
3.2Gbps VCSEL Driver with Diagnostic Monitors
3.2Gbps, K28.5, 10mA MODULATION, PEAKING
ELECTRICAL
OPTICAL
50ps/div
MAX3740A toc01
MAX3740A toc04
73mV/div
ELECTRICAL WITH PEAKING
3.2Gbps, K28.5, 10mA MODULATION, RPEAKSET 2.4k
OPTICAL
50ps/div
Typical Operating Characteristics
MAX3740A toc05
MAX3740A toc02
73mV/div
ELECTRICAL WITH PEAKING
IBIASMON BIAS CURRENT
3.2Gbps, K28.5, 10mA MODULATION, RPEAKSET
50ps/div
MAX3740A toc03
MAX3740A toc06
8.2dB, 2.125Gbps, K28.5, 850nm VCSEL, WITH 2.3GHz O-TO-E CONVERTER
68ps/div
RANDOM JITTER MODULATION CURRENT
EMCORE SC-TOSA-8585-3420 VCSEL
8.2dB, 2.5Gbps, K28.5, 850nm VCSEL SONET MASK WITH +20% MARGIN
58ps/div
IBIASMON (mA)
TRANSITION TIME MODULATION CURRENT
BIAS CURRENT (mA)
MAX3740A toc09
IMOD (mAP-P)
IMOD (mAP-P) IMOD (mAP-P) RISE FALL
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3.2Gbps VCSEL Driver with Diagnostic Monitors
MODULATION CURRENT (mAP-P) SUPPLY CURRENT (mA) BIAS CURRENT
MAX3740A toc17
MAX3740A
(VCC +3.3V, PEAKSET open, measured electrically with load AC-coupled OUT+, +25°C, unless otherwise noted.)
100m
100µ
MODULATION CURRENT (AP-P)
MAX3740A toc11
MAX3740A toc10
BIAS CURRENT RBIASSET
100m
Typical Operating Characteristics (continued)
MODULATION CURRENT RMODSET
MONITOR DIODE CURRENT RPWRSET
MAX3740A toc12
MEASURED WITH ELECTRICAL LOAD
MONITOR DIODE CURRENT
SUPPLY CURRENT TEMPERATURE
RBIASSET
100k
INPUT RETURN LOSS
RMODSET
100µ
OUTPUT RETURN LOSS
RPWRSET
MAX3740A toc15
MAX3740A toc14
MAX3740A toc13
IMOD 15mA
(dB)
(dB)
MODULATION CURRENT TEMPERATURE
TEMPERATURE (°C)
IMOD
5500
100M
MODULATION CURRENT TEMPCO
FREQUENCY (Hz)
DIFFERENTIAL MEASUREMENT
100M
MONITOR DIODE CURRENT TEMPERATURE
FREQUENCY (Hz)
SINGLE-ENDED MEASUREMENT
MAX3740A toc18
MAX3740A toc16
RMOD 1.35k 4500 MONITOR DIODE CURRENT (µA) TEMPCO (ppm/°C) 500k 100k TEMPERATURE (°C) 1500 2500 3500 -500 REFERENCED +25°C 100k
TEMPERATURE (°C)
MAX3740A
TX_DISABLE
LASER OUTPUT
(VCC +3.3V, PEAKSET open, measured electrically with load AC-coupled OUT+, +25°C, unless otherwise noted.)
FAULT
PLUG WITH TX_DISABLE
TX_DISABLE
TX_DISABLE
VPWRMON
LASER OUTPUT
3.2Gbps VCSEL Driver with Diagnostic Monitors
LASER OUTPUT
FAULT
FAULT
t_INIT 60ms
20ms/div
HIGH 3.3V
TRANSMITTER DISABLE
FAULT RECOVERY TIME
MAX3740A toc19
EXTERNAL FAULT REMOVED
1µs/div
40µs/div
t_OFF 1.86µs
TX_DISABLE
3.3V
HIGH
t_INIT 54µs
LASER OUTPUT
FAULT
HIGH
MAX3740A toc22
MAX3740A toc24
Typical Operating Characteristics (continued)
STARTUP WITH SLOW RAMPING SUPPLY
20ms/div
t_INIT 62ms
3.3V
TX_DISABLE
TX_DISABLE
MAX3740A toc20
VPWRMON
EXTERNALLY FORCED VPWRMON FAULT
LASER OUTPUT
LASER OUTPUT
FAULT
FAULT
FREQUENT ASSERTION TX_DISABLE
TX_DISABLE
EXTERNALLY FORCED FAULT
LASER OUTPUT
RESPONSE FAULT
FAULT
t_FAULT 245ns
200µs/div
200ns/div
HIGH
TX_DISABLE NEGATE TIME
t_ON 54µs
HIGH
MAX3740A toc25
MAX3740A toc23
20µs/div
3.3V
MAX3740A toc21
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3.2Gbps VCSEL Driver with Diagnostic Monitors
MAX3740A
Exposed TX_DISABLE SQUELCH BIASMON PWRMON PEAKSET MODSET BIASSET FAULT COMP NAME OUT+ OUTGND BIAS INInverted Data Input Monitor Diode Connection Ground +3.3V Supply Voltage Bias Current Output Inverted Modulation-Current Output Noninverted Data Input Noninverted Modulation-Current Output FUNCTION
Temperature Compensation resistor placed between (RTC) programs temperature coefficient modulation current.
Temperature Compensation resistor placed between (RTC) programs temperature coefficient modulation current.
Fault Indicator. Open-drain output with protection. FAULT asserted high during fault condition.
Average Power Monitor. used monitor transmit optical power. open-loop configuration, connect PWRMON GND. Reference Pin. Reference monitor used APC. resistor between (RPWRSET) sets photo monitor current when loop closed. Compensation Pin. capacitor between COMP compensates APC. typical value 0.047µF recommended. open-loop configuration, short COMP deactivate APC. Bias Current Monitor. output BIASMON sourced current proportional bias current. resistor connected between BIASMON ground (RBIASMON) used form groundreferenced bias monitor. Bias Current Set. When closed-loop configuration used, connect 1.7k resistor between ground BIASSET maximum bias current. When open configuration used, connect resistor between BIASSET ground (RBIASSET) program VCSEL bias current. Peaking Current Set. resistor connected between PEAKSET ground (RPEAKSET) programs peaking current amplitude. disable peaking, leave PEAKSET open. Modulation Set. resistor connected from MODSET ground (RMODSET) sets desired modulation current amplitude. Squelch Enable. Squelch enabled when high. Squelch disabled when left open. Transmit Disable. Driver output disabled when TX_DISABLE high left unconnected. driver output enabled when asserted low.
Ground. Must soldered circuit board ground proper thermal electrical performance. Layout Considerations section.
Description
MAX3740A
Figure shows bias generator circuitry that contains power-control amplifier smooth-start circuitry. internal transistor provides laser current bias laser light-emitting state. circuitry adjusts laser-bias current maintain average power over temperature changing laser properties. smooth-start circuitry prevents current spikes laser during power-up enable, ensuring compliance with safety requirements extending life laser. input connected cathode monitor diode, which used sense laser power. BIAS output connected anode laser through inductor ferrite bead. power-control amplifier drives current amplifier control laser's bias current. During fault condition, bias current disabled. PWRMON output provides voltage proportional average laser power given VPWRMON RPWRSET
MAX3740A contains bias generator with automatic power control (APC), safety circuit, laser modulator with optional peaking compensation.
Figure Bias Generator
RPWRSET
3.2Gbps VCSEL Driver with Diagnostic Monitors
Detailed Description
SMOOTHSTART
CCOMP
1.8V
1.6V (2VBE)
Bias Generator
POWERCONTROL AMPLIFIER
PWRMON
COMP
MAX3740A
BIAS GENERATOR
1.2V
safety circuit contains input disable (TX_DISABLE), latched fault output (FAULT), fault detectors (Figure This circuit monitors operation laser driver forces shutdown (disables laser) fault detected (Table Table contains circuit's response various single-point failures. transmit fault condition latched until reset toggle TX_DISABLE VCC. FAULT should pulled high with 4.7k resistor.
IBIASMON IBIAS When used monitor diode, open-loop configuration) connect COMP PWRMON pins GND. this mode, bias current resistor RBIASSET. When closed-loop configuration used, connect 1.7k resistor between ground BIASSET maximum bias current.
BIASMON output provides current proportional laser bias current given
Table Fault Conditions
PWRMON
BIASMON
BIAS
IBIAS
CURRENT AMPLIFIER
BIASSET
RBIASSET
IBIAS
ENABLE
VBIASMON 0.8V
VBIAS 0.2V
VPWRMON 0.8V
BIASMON
BIAS
FAULT CONDITION
RBIASMON
Safety Circuit
FERRITE BEAD
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3.2Gbps VCSEL Driver with Diagnostic Monitors MAX3740A
Table Circuit Response Various Single-Point Faults (Closed-Loop Configuration)
NAME FAULT TX_DISABLE INSQUELCH MODSET PEAKSET OUT+ OUTBIASSET BIAS BIASMON COMP CIRCUIT RESPONSE SHORT Does affect laser power. Modulation bias current disabled. Does affect laser power. Does affect laser power. Does affect laser power. Does affect laser power. laser modulation increased, average power affected. Modulation current disabled. Does affect laser power. Modulation current disabled. Does affect laser power. Laser bias disabled. Fault state* occurs. Note that VCSEL emissions continue; care must taken prevent this condition. Fault state* occurs. bias current reduced, average power laser output reduced. IBIAS increases value determined RBIASSET; bias-monitor fault threshold exceeded, fault signaled. IBIAS increases value determined RBIASSET; bias-monitor fault threshold exceeded, fault signaled. Fault state* occurs. CIRCUIT RESPONSE SHORT Does affect laser power. Normal condition circuit operation. Does affect laser power. Does affect laser power. Does affect laser power. Does affect laser power. Modulation current disabled. laser modulation increased, average power affected. Does affect laser power. Modulation current disabled. Does affect laser power. Fault state* occurs. Disables VCSEL. Does affect laser power. IBIAS increases value determined RBIASSET; bias monitor fault threshold exceeded, fault signaled. bias current reduced, average power laser output reduced.
PWRMON
bias current reduced, average power laser output reduced. Does affect laser power.
fault state asserts FAULT pin, disables modulator output, disables bias output.
Modulation Circuit
modulation circuitry consists input buffer, current mirror, high-speed current switch (Figure modulator drives 15mA modulation into VCSEL load. amplitude modulation current with resistors MODSET temperature coefficient (TC1, TC2) pins. resistor MODSET MODSET) programs temperature-stable portion modulation current, resistor between (RTC) programs temperature coefficient modulation current. appropriate RMODSET values, Typical Operating Characteristics section.
Design Procedure
Select Laser
Select communications-grade laser with rise time 260ps better 1.25Gbps, 130ps better 2.5Gbps applications. high-efficiency laser that requires modulation current generates lowvoltage swing. Trim leads reduce laser package inductance. typical package leads have inductance 25nH inch (1nH/mm). This inductance causes large voltage swing across laser. compensation filter network also used reduce ringing, edge speed, voltage swing (see Designing Compensation Filter Network section).
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MAX3740A
Figure Modulation Circuit Figure Safety Circuit
SQUELCH
TX_DISABLE
TX_DISABLE
PWRMON
BIASMON
BIAS
3.2Gbps VCSEL Driver with Diagnostic Monitors
MAX3740A
INPUT BUFFER
0.2V 0.8V 0.8V
TEMPERATURE COMPENSATION SIGNAL DETECT ENABLE
HIGH-CURRENT FAULT
HIGH-POWER FAULT
VBIAS FAULT
CURRENT SWITCH
ROUT-
CURRENT AMPLIFIER
MODSET RMODSET
ROUT+
LATCH
SAFETY CIRCUIT
MODULATION CURRENT GENERATOR
PEAKING CONTROL
MAX3740A
FAULT OUTPUT
OUT+
OUT-
PEAKSET
ENABLE
FAULT
RPEAKSET
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Bias Current RBIASSET graph also shown Typical Operating Characteristics.
bias current output MAX3740A controlled resistor (RBIASSET) placed between BIASSET ground. open-loop operation RBIASSET controls bias current level VCSEL. closed-loop operation RBIASSET controls maximum bias current provided APC. bias current given following:
typical 400µA, RPWRSET 500, select photodiode with capacitance less than 500pF.
MAX3740A
modulation current output MAX3740A controlled resistor MODSET placed between MODSET ground. RMODSET resistor controls amount current being sourced VCSEL. modulation current given following:
important note that modulation current being sourced MAX3740A affected load impedance VCSEL. Modulation Current RMODSET graph Typical Operating Characteristics shows current into electrical load.
Compute required modulation tempco from slope efficiency laser +25°C higher temperature. Then select value from Typical Operating Characteristics. example, suppose laser slope efficiency (SE) ensure stable operation circuit, time constant node should shorter than time constant. (tAPC CAPC 0.047µF). ROUT+ IMOD (IMODSET ROUT+ RLOAD ROUT+ IMOD RMODSET OUT+ RLOAD
3.2Gbps VCSEL Driver with Diagnostic Monitors
Programming Modulation-Current Tempco
250ns
IBIAS RBIASSET
IBIAS (IBIASSET
Programming Modulation Current
Programming Bias Current
Photodiode Selection
From Typical Operating Characteristics, value RTC, which offsets tempco laser, modulation temperature compensation desired, short TC2.
0.021mW/mA +25°C, which reduces 0.018mW/mA +85°C. temperature coefficient given following:
MAX3740A data inputs compatible. On-chip differential input impedance provided optimal termination (Figure Because on-chip biasing network, MAX3740A inputs self-bias proper operating point accommodate AC-coupling.
Program average optical power adjusting PWRSET select resistance, determine desired monitor current maintained over temperature lifetime. Monitor Diode Current RPWRSET graph Typical Operating Characteristics section, select value RPWRSET that corresponds required current.
Figure Simplified Input Structure
Laser tempco
PACKAGE
MAX3740A
0.5pF 0.5pF
Input Termination Requirements
(SE85 SE25 SE25 -2380ppm
Programming Loop
MAX3740A
Laser package inductance causes laser impedance increase high frequencies, leading ringing, overshoot, degradation laser output. laser compensation filter network used reduce laser impedance high frequencies, thereby reducing output ringing overshoot. minimize inductance, keep connections between MAX3740A output pins laser diode short possible. good high-frequency layout techniques multilayer boards with uninterrupted ground planes minimize crosstalk. Figures show simplified input output circuits MAX3740A laser driver. Figure shows fault circuit interface.
Figure Fault Circuit Interface Figure Simplified Output Structure
ROUT-
MAX3740A
3.2Gbps VCSEL Driver with Diagnostic Monitors
Designing Compensation Filter Network
ROUT+
Applications Information
Layout Considerations
Interface Models
PACKAGE
MAX3740A
0.5pF
OUT-
POWER
0.5pF
FAULT
OUT+
International Electrotechnical Commission (IEC) determines standards hazardous light emissions from fiber optic transmitters. defines maximum light output various hazard levels. MAX3740A provides features that facilitate compliance with 825. common safety precaution single-point fault tolerance, whereby unplanned short, open, resistive connection does cause excess light output. Using this laser driver alone does ensure that transmitter design compliant with 825. entire transmitter circuit component selections must considered. Customers must determine level fault tolerance required their applications, recognizing that Maxim products designed authorized components systems intended surgical implant into body, applications intended support sustain life, other application where failure Maxim product could create situation where personal injury death occur. exposed 24-pin thin provides very thermal resistance path heat removal from also electrical ground MAX3740A must soldered circuit board ground proper thermal electrical performance. Refer Maxim Application Note HFAN-08.1: Thermal Considerations Other Exposed-Pad Packages additional information. compensation components most easily determined experimentation. Begin with 1pF. Increase until desired transmitter response obtained (Figure Refer Application Note HFAN-2-0: Interfacing Maxim Laser Drives with Laser Diodes more information.
Figure Laser Compensation
Exposed-Pad (EP) Package
Laser Safety
CORRECTLY COMPENSATED
UNCOMPENSATED
OVERCOMPENSATED
TIME
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2004 Maxim Integrated Products
_Maxim Integrated Products, Gabriel Drive, Sunnyvale, 94086 408-737-7600
Maxim cannot assume responsibility circuitry other than circuitry entirely embodied Maxim product. circuit patent licenses implied. Maxim reserves right change circuitry specifications without notice time.
latest package outline information, www.maxim-ic.com/packages.
3.2Gbps VCSEL Driver with Diagnostic Monitors
TRANSISTOR COUNT: 3806 PROCESS: SiGe BIPOLAR
MAX3740AETG
PART
Thin (4mm 0.8mm)
PACKAGE TYPE
MAX3740A
TX_DISABLE
SQUELCH
Package Information
Chip Information
FAULT
SAFETY CIRCUITRY
MAX3740A
Printed
PACKAGE CODE T2444-1
ENABLE SIGNAL DETECT
@@@@@@@@@?f(@@@@@@7 e@@@@@@@2W?f?@@@@@@@2W
COMP
ENABLE
MODULATION CURRENT GENERATOR
TX_DISABLE
registered trademark Maxim Integrated Products.
SQUELCH *EXPOSED CONNECTED PWRMON
PWRMON MODSET BIAS GENERATOR WITH LASER MODULATOR BIASMON PEAKING CONTROL PEAKSET
Functional Diagram
Configuration
OUTOUT+
BIASSET
BIAS
BIASMON
VIEW
FAULT
THIN (4mm 4mm)
PEAKSET
MODSET
MAX3740A
OUTOUT+ BIASSET BIAS
COMP
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