MAX3795ETG+T ,1Gbps to 4.25Gbps Multirate VCSEL Driver with Diagnostic Monitorsfeatures.♦ 2mA to 15mA Modulation CurrentThe automatic power control (APC) adjusts the laser♦ 1mA t ..
MAX3798ETJ+ ,1.0625Gbps to 10.32Gbps, Integrated, Low-Power SFP+ Limiting Amplifier and VCSEL DriverFeaturesThe MAX3798 is a highly integrated limiting amplifier♦ Low Power Dissipation of 320mW at 3. ..
MAX3799ETJ+ ,1Gbps to 14Gbps, SFP+ Multirate Limiting Amplifier and VCSEL Driverapplications.♦ -21.5dBm Optical Sensitivity at 1.25Gbps Using aBy providing a selectable data path ..
MAX379CPE ,High-Voltage, Fault-Protected Analog MultiplexersMAX378/MAX37919-1902; Rev 1; 8/94High-Voltage, Fault-ProtectedAnalog Multiplexers_______________
MAX379CPE ,High-Voltage, Fault-Protected Analog MultiplexersApplicationsMAX378MJE -55°C to +125°C 16 CERDIPData Acquisition SystemsMAX378MLP -55°C to +125°C 20 ..
MAX379CPE ,High-Voltage, Fault-Protected Analog MultiplexersApplicationsMAX378MJE -55°C to +125°C 16 CERDIPData Acquisition SystemsMAX378MLP -55°C to +125°C 20 ..
MAX737CPD ,-5V,-12V,-15V, and Adjustable Inverting Current-Mode PWM Regulatorsfeatures, along with
high efficiency and an application circuit that lends itself to
miniaturizat ..
MAX737CWE ,-5V,-12V,-15V, and Adjustable Inverting Current-Mode PWM RegulatorslVI/lXI/VI
-5V, -12V, -15V, and Adjustable
Inverting Gurrent-Mode PWM Regulators
MAX737CWE+T ,-12V, Inverting, PWM, Current-Mode DC-DC ConverterELECTRICAL CHARACTERISTICS
Bootstrapped Mode (Circuit of Figure 1, V+ = w, ILOAD = 0mA, DRV- = V ..
MAX737EPD ,-5V,-12V,-15V, and Adjustable Inverting Current-Mode PWM RegulatorsELECTRICAL CHARACTERISTICS
Bootstrapped Mode (Circuit of Figure 1, V+ = w, ILOAD = 0mA, DRV- = V ..
MAX7381AXR166+T ,3-Pin Silicon OscillatorApplicationsPART TEMP RANGE PIN-PACKAGEWhite GoodsMAX7381AXR106-T -40°C to +125°C 3 SC70-3Automotiv ..
MAX7384CRUK ,10 MHz, 2.7 V to 5.5 V, silicon oscillator with low-power frequency switching and reset outputfeatures a factory-programmed high-speed♦ Integrated PORoscillator, a 32.768kHz oscillator, a clock ..
MAX3795ETG+T
1Gbps to 4.25Gbps Multirate VCSEL Driver with Diagnostic Monitors
General DescriptionThe MAX3795 is a high-speed VCSEL driver for small-
form-factor (SFF) and small-form-factor pluggable (SFP)
fiber optic transmitters. It contains a bias generator, a
laser modulator, and comprehensive safety features.
The automatic power control (APC) adjusts the laser
bias current to maintain average optical power over
changes in temperature and laser properties. The dri-
ver accommodates common-cathode and differential
configurations.
The MAX3795 operates up to 4.25Gbps. It can switch
up to 15mA of laser modulation current and source up
to 15mA of bias current. Adjustable temperature com-
pensation is provided to keep the optical extinction
ratio within specifications over the operating tempera-
ture range. The MAX3795 interfaces with the Dallas
DS1856/DS1859 to meet SFF-8472 timing and diagnos-
tic requirements. The MAX3795 accommodates various
VCSEL packages, including low-cost TO-46 headers.
The MAX3795 safety circuit detects faults that could
cause hazardous light levels and disables the VCSEL
output. The safety circuits are compliant with SFF and
SFP multisource agreements (MSAs).
The MAX3795 is available in a compact 4mm ✕4mm,
24-pin thin QFN package and operates over the -40°C
to +85°C temperature range. The MAX3795 is pin-for-
pin compatible with the MAX3740A and is available in
lead-free packages.
ApplicationsMultirate (1Gbps to 4.25Gbps) SFP/SFF Modules
Gigabit Ethernet Optical Transmitters
Fibre-Channel Optical Transmitters
FeaturesSupports All SFF-8472 Digital Diagnostics 3.3V ±10% Single Supply2mA to 15mA Modulation Current1mA to 15mA Bias Current52ps Transition Time8.4ps Deterministic JitterOptional Peaking Current to Improve VCSEL Edge
SpeedSupports Common-Cathode and Differential
ConfigurationSafety Circuits Compliant with SFF and SFP
MSAsPin Compatible to MAX3740A
MAX3795
1Gbps to 4.25Gbps Multirate VCSEL
Driver with Diagnostic Monitors
Ordering Information19-3387; Rev 0; 8/04
PARTTEMP RANGEPIN-PACKAGEMAX3795ETG-40°C to +85°C24 Thi n QFN ( 4m m x 4m m )
MAX3795ETG+-40°C to +85°C24 Thi n QFN ( 4m m x 4m m ) 2322212019
PWRMONREFMDCOMPV
BIASMON891112
TC1TC2
GND
MODSET
PEAKSET
EXPOSED PAD IS CONNECTED TO GND
GND
OUT-
OUT+
VCC
BIASSET
BIAS
SQUELCH
FAULT
IN-
IN+
TX_DISABLE
GND
MAX3795
THIN QFN (4mm x 4mm)TOP VIEW
Pin Configuration+Denotes lead-free package.
MAX3795
1Gbps to 4.25Gbps Multirate VCSEL Driver
with Diagnostic Monitors
ABSOLUTE MAXIMUM RATINGSStresses 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.
Supply Voltage (VCC)............................................-0.5V to +4.0V
Voltage at TX_DISABLE, IN+, IN-, FAULT,
SQUELCH, TC1, TC2, MODSET, PEAKSET, BIASSET,
BIAS, BIASMON, COMP, MD, REF,
PWRMON ...............................................-0.5V to (VCC+ 0.5V)
Voltage at OUT+, OUT-.........................(VCC- 2V) to (VCC+ 1V)
Current into FAULT............................................-1mA to +25mA
Current into OUT+, OUT-....................................................60mA
Continuous Power Dissipation (TA= +85°C)
24-Pin Thin QFN
(derate 20.8mW/°C above +85°C).................................1354mW
Storage Temperature Range.............................-55°C to +150°C
Lead Temperature (soldering, 10s).................................+300°C
ELECTRICAL CHARACTERISTICS(VCC= +2.97V to +3.63V, TA= -40°C to +85°C. Typical values are at VCC= +3.3V, TC1 and TC2 are shorted, PEAKSET open, TA=
+25°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSIMOD = 2mAP-P35SQUELCH set low,
TX_DISABLE set low,
peaking is not used
(Note 1)IMOD = 15mAP-P7181
Additional current when peaking is used,
RPEAK = 1.18kΩ15
ICC
Additional current when SQUELCH is high510
Supply Current
ICC-SHDNTotal current when TX_DISABLE is high7
FAULT OUTPUTOutput High VoltageVOHRLOAD = 10kΩ to 2.97V2.4V
Output Low VoltageVOLRLOAD = 4.7kΩ to 3.63V0.4V
TX_DISABLE INPUTInput ImpedanceRPULL4.7810.0kΩ
Input High VoltageVIH2.0V
Input Low VoltageVIL0.8V
Power-Down TimeThe time for ICC to reach ICC-SHDN when
TX_DISABLE transitions high50µs
SQUELCHSquelch Threshold2585mVP-P
Squelch Hysteresis6mVP-P
Time to Squelch Data(Note 3)0.025.00µs
Time to Resume from Squelch(Note 3)0.025.00µs
BIAS GENERATORMaximum Bias Pin VoltageVBIAS-MAXReferenced to VCC-0.65V
Minimum1Bias CurrentIBIASMaximum15mA
5mA ≤ IBIAS ≤ 15mA-8+8Accuracy of Programmed Bias
Current∆BIAS1mA ≤ IBIAS ≤ 5mA-12+12%
MAX3795
1Gbps to 4.25Gbps Multirate VCSEL Driver
with Diagnostic Monitors
ELECTRICAL CHARACTERISTICS (continued)(VCC= +2.97V to +3.63V, TA= -40°C to +85°C. Typical values are at VCC= +3.3V, TC1 and TC2 are shorted, PEAKSET open, TA=
+25°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITSBias Current During FaultIBIAS_OFFCurrent out of the BIAS pin1.510µA
1mA < IBIAS < 3mA0.08750.1050.1375BIASMON GainGBIASMONIBIASMON / IBIAS3mA ≤ IBIAS < 15mA0.0850.1050.125mA/mA
BIASMON Stability(Notes 2, 4)-10+10%
AUTOMATIC POWER CONTROL (APC)MD Nominal VoltageVMDAPC loop is closed1VREF -
0.22V
Voltage at REFVREF1.21.82.2V
MD Voltage During Fault0V
MD Input CurrentNormal operation (FAULT = low)-20.7+2µA
APC Time ConstantCCOMP = 0.047µF, ∆IPD / ∆ILASER = 0.0290µs
PWRMON Nominal GainVPWRMON / (VREF - VMD)1.852.152.45V/V
LASER MODULATOR (Load is 50Ω AC-Coupled to OUT+)Minimum0.25Differential Input VoltageVIDMaximum2.4VP-P
Input Common-Mode VoltageVCM1.75V
Differential Input ResistanceRIN85100115Ω
Single-Ended Input Return LossS11f < 4GHz12.7dB
Differential Input Return LossSDD11f < 4GHz11dB
Minimum2Modulation CurrentIMODCurrent into OUT+
RLOAD ≤ 50ΩMaximum15mA
Laser Modulation During Fault or
Squelch ActiveIMOD_OFFDC tested1550µAP-P
Tolerance of Programmed
Modulation CurrentTC1 is shorted to TC2-10+10%
Minimum Peaking CurrentRPEAKSET = 10kΩ0.2mA
Maximum Peaking CurrentRPEAKSET = 1kΩ2mA
Peaking Current Duration75ps
Output ResistanceROUTSingle-ended resistance425058Ω
Minimum Programmable
Temperature Coefficient0ppm/°C
Maximum Programmable
Temperature CoefficientTemperature range 0°C to +70°C+5000ppm/°C40°C to + 85° C 4972tR50Ω load, no peaking,
5mA ≤ IMOD ≤ 15mA+100°C5840°C to + 85° C 5679
Modulation Transition Time
(Note 2)tF50Ω load, no peaking,
5mA ≤ IMOD ≤ 15mA+100°C64
MAX3795
1Gbps to 4.25Gbps Multirate VCSEL Driver
with Diagnostic Monitors
ELECTRICAL CHARACTERISTICS (continued)(VCC= +2.97V to +3.63V, TA= -40°C to +85°C. Typical values are at VCC= +3.3V, TC1 and TC2 are shorted, PEAKSET open, TA=
+25°C, unless otherwise noted.)
PARAMETERSYMBOLCONDITIONSMINTYPMAXUNITS40°C to + 85° C 8.415.6Deterministic JitterDJ5m A ≤ IM OD ≤ 15m A,
4.25G b p s, K28.5 ( N otes 2, 5) +100°C12.7psP-P
APC closed loop0.5Random JitterRJAPC open loop (Note 2)0.50.9psRMS
SAFETY FEATURES (see the Typical Operating Characteristics)High-Current Fault ThresholdVBMTHVBIASMON > VBMTH causes a fault0.70.80.9V
VBIAS Fault ThresholdVBTHVBIAS referenced to VCC-0.250-0.2-0.150V
Power-Monitor Fault ThresholdVPMTHVPWRMON > VPMTH causes a fault0.70.80.9V
TX Disable Timet_OFF
Time from rising edge of TX_DISABLE to
IBIAS = IBIAS_OFF and IMOD = IMOD_OFF
(Note 2)
1.85µs
TX Disable Negate Timet_ON
Time from rising edge of TX_DISABLE to
IBIAS and IMOD at 99% of steady state
(Note 2)500µs
Fault Reset Timet_INIT1Time to set VFAULT = low after power-on or
after rising edge of TX_DISABLE (Note 2)60200ms
Power-On Timet_INIT2Time after power-on to transmitter-on with
TX_DISABLE low (Note 2)60200ms
Fault Assert Timet_FAULT
Time from fault occurrence to VFAULT =
high; CFAULT < 20pF, RFAULT = 4.7kΩ
(Note 2)
1.450µs
Fault Delay Timet_FLTDLY
Time from fault to IBIAS = IBIAS_OFF and
IMOD = IMOD_OFF; measured with a
continuously occurring fault (Note 2)µs
TX_DISABLE Resett_RESETTime TX_DISABLE must be held high to
reset FAULT (Note 2)1µs
Note 1:Supply current measurements exclude IBIASfrom the total current.
Note 2:AC characteristics guaranteed by design and characterization.
Note 3:Measured by applying a pattern that contains 20µs of K28.5, followed by 5µs of zeros, then 20µs of K28.5, followed by 5µs
of ones. Data rate is equal to 2.5Gbps, with inputs filtered using 1.8GHz Bessel filters.
Note 4:Variation of bias monitor gain for any single part over the range of VCC, temperature, 3mA < IBIAS< 15mA.
Note 5:Deterministic jitter measured at 4.25Gbps with a K28.5 pattern (00111110101100000101).
MAX3795
1Gbps to 4.25Gbps Multirate VCSEL Driver
with Diagnostic Monitors
ELECTRICAL EYE DIAGRAMMAX3795 toc01
40ps/div
75mV/div
4.25Gbps, K28.5, 10mA MODULATION,
PEAKING OFF
ELECTRICAL EYE DIAGRAMMAX3795 toc02
152ps/div
75mV/div
1Gbps, K28.5, 10mA MODULATION,
RPEAKSET = 1.4kΩ
OPTICAL EYE DIAGRAMMAX3795 toc03
135ps/div
1Gbps, K28.5, -3dBm, 850nm VCSEL
ADVANCED OPTICAL COMPONENTS,
HFE4191-541
OPTICAL EYE DIAGRAMMAX3795 toc04
34ps/div
4.25Gbps, K28.5, -7dBm, 850nm VCSEL,
ADVANCED OPTICAL COMPONENTS
HFE4191-541
OPTICAL EYE DIAGRAMMAX3795 toc05
50ps/div
3.125Gbps, K28.5, -7dBm, 850nm VCSEL,
ADVANCED OPTICAL COMPONENTS
HFE4191-541
IBIASMON vs. BIAS CURRENTMAX3795 toc06
BIAS CURRENT (mA)
IBIASMON
(mA)84
DETERMINISTIC JITTER
vs. MODULATION CURRENT
MAX3795 toc07
MODULATION CURRENT (mAP-P)
DETERMINISTIC JITTER (ps
P-P468101214161820
RANDOM JITTER
vs. MODULATION CURRENTMAX3795 toc08
MODULATION CURRENT (mAP-P)
RANDOM JITTER (ps
RMS
IBIAS = 5mA
TRANSITION TIME
vs. MODULATION CURRENTMAX3795 toc09
MODULATION CURRENT (mA)
TRANSITION TIME (ps)468101214
MEASURED FROM 20%
FALL TIME
RISE TIME
Typical Operating Characteristics(VCC= +3.3V, RTC= 0Ω, PEAKSET open, measured electrically with a 50Ωload AC-coupled to OUT+, TA= +25°C, unless otherwise
noted.)
