100G QSFP28 SR4

The 100G-QSFP28-SR4 is a Four-Channel, Pluggable, Parallel, Fiber-Optic QSFP28 Transceiver for IEEE 802.3bm, 100GBASE SR4 Applications,or 40 Gigabit Ethernet and Infiniband FDR/EDR Applications. The QSFP28 full-duplex optical module offers 4 independent transmit and receive channels, each capable of 26Gbps operation for an aggregate data rate of 104Gbps 70m using OM3 fiber. These 100G-QSFP28-SR4 are designed to operate over multimode fiber systems using 850nm VCSEL laser array. An 11 optical fiber ribbon cable with an MPO/MTPTM connector can be plugged into the QSFP module receptacle. QSFP28 SR4 is one kind of parallel transceiver which provides increased port density and total system cost savings.

100G-QSFP28-SR4 Features
Four-channel full-duplex transceiver modules
Transmission data rate up to 26Gbit/s per channel
Up to 70m on OM3 Multimode Fiber (MMF)and 100m on OM4 MMF
Low power consumption <3.5W
Operating case temperature 0°C to +70°C
3.3V power supply voltage
RoHS 6 compliant
Hot Pluggable QSFP form factor
MPO connector receptacle
Built-in digital diagnostic function

100G-QSFP28-SR4 Applications
IEEE 802.3bm 100GBASE SR4 and 40GBASE SR4
Proprietary High Speed Interconnections
Data center

Absolute Maximum Ratings
The operation in excess of any absolute maximum ratings might cause permanent damage to this module.

Storage TemperatureTST-4085degC
Relative Humidity(non-condensing)RH085%
Operating Case TemperatureTOPC070degC
Supply VoltageVCC-0.33.6V
Input VoltageVin-0.3Vcc+0.3V

Recommended Operating Conditions and Supply Requirements

Operating Case TemperatureTOPC070degC
Power Supply VoltageVCC3.133.33.47V
Power Consumption3.5W
Data RateDR25.78125Gbps
Data Speed Tolerance∆DR-100+100ppm
Link Distance with OM3 fiberD070m

Optical Characteristics
All parameters are specified under the recommended operating conditions with PRBS31 data pattern unless otherwise specified.

Center WavelengthλC840850860nm1
RMS Spectral Widthλrms0.65nm1
Average Launch Power, each lanePAVG-7-2.50dBm
Optical Modulation AmplitudePOMA-5-2.50dBm1


Difference in Launch Power between any two lanesPtx,diff4.0dB
Launch Power in OMA minus

Transmitter and Dispersion

Penalty (TDP), each Lane

Extinction RatioER3.5dB
Transmitter Eye Mask MarginEMM10%2
Average Launch Power OFF

Transmitter, each Lane

Transmitter Eye Mask

Definition {X1, X2, X3, Y1, Y2,


{0.3, 0.38, 0.45, 0.35, 0.41, 0.5}
Center WavelengthλC840850860nm
Damage ThresholdTHd+3dBm
Overload, each laneOVL+2.4dBm
Receiver Sensitivity in OMA, each LaneSEN-10.3dBm
Signal Loss Assert ThresholdLOSA-30dBm
Signal Loss Deassert ThresholdLOSD-9dBm
LOS HysteresisLOSH0.56dB
Optical Return LossORL-12dBm


  1. Transmitter wavelength, RMS spectral width and power need to meet the OMA minus TDP specs to guarantee link performance.
  2. The eye diagram is tested with 1000 waveform.

Electrical Specifications

Differential input impedanceZin90100110ohm


Differential Output impedanceZout90100110ohm
Differential input voltage amplitudeΔVin3001100mVp-p
Differential output voltage amplitudeΔVout500800mVp-p
Bit Error RateBRE-12
Input Logic Level HighVIH2.0VCCV
Input Logic Level LowVIL00.8V
Output Logic Level HighVOHVCC-0.5VCCV
Output Logic Level LowVOL00.4V

Pin Descriptions

2CML-ITx2nTransmitter Inverted Data Input
3CML-ITx2pTransmitter Non-Inverted Data output
5CML-ITx4nTransmitter Inverted Data Input
6CML-ITx4pTransmitter Non-Inverted Data output
8LVTLL-IModSelLModule Select
9LVTLL-IResetLModule Reset
10VccRx﹢3.3V Power Supply Receiver2
11LVCMOS-I/OSCL2-Wire Serial Interface Clock
12LVCMOS-I/OSDA2-Wire Serial Interface Data
14CML-ORx3pReceiver Non-Inverted Data Output
15CML-ORx3nReceiver Inverted Data Output
17CML-ORx1pReceiver Non-Inverted Data Output
18CML-ORx1nReceiver Inverted Data Output
21CML-ORx2nReceiver Inverted Data Output
22CML-ORx2pReceiver Non-Inverted Data Output
24CML-ORx4nReceiver Inverted Data Output1


25CML-ORx4pReceiver Non-Inverted Data Output
27LVTTL-OModPrsLModule Present
29VccTx+3.3 V Power Supply transmitter2
30Vcc1+3.3 V Power Supply2
31LVTTL-ILPModeLow Power Mode
33CML-ITx3pTransmitter Non-Inverted Data Input
34CML-ITx3nTransmitter Inverted Data Output
36CML-ITx1pTransmitter Non-Inverted Data Input
37CML-ITx1nTransmitter Inverted Data Output


  1. Module circuit ground is isolated from module chassis ground within the module. GND is the symbol for signal and supply (power) common for QSFP modules.
  2. The connector pins are each rated for a maximum current of 500mA.

ModSelL Pin
The ModSelL is an input pin. When held low by the host, the module responds to

2-wire serial communication commands. The ModSelL allows the use of multiple QSFP


modules on a single 2-wire interface bus. When the ModSelL is “High”, the module will not respond to any 2-wire interface communication from the host. ModSelL has an internal pull-up in the module.
ResetL Pin
Reset. LPMode_Reset has an internal pull-up in the module. A low level on the ResetL pin for longer than the minimum pulse length (t_Reset_init) initiates a complete module reset, returning all user module settings to their default state. Module Reset Assert Time (t_init) starts on the rising edge after the low level on the ResetL pin is released. During the execution of a reset (t_init) the host shall disregard all status bits until the module indicates a completion of the reset interrupt. The module indicates this by posting an IntL signal with the Data_Not_Ready bit negated. Note that on power up (including hot insertion) the module will post this completion of reset interrupt without requiring a reset.
LPMode Pin
Huihongfiber QSFP28 SR4 operate in the low power mode (less than 1.5 W power consumption) This pin active high will decrease power consumption to less than 1W.
ModPrsL Pin
ModPrsL is pulled up to Vcc on the host board and grounded in the module. The ModPrsL is asserted “Low” when the module is inserted and deasserted “High” when the module is physically absent from the host connector.
IntL Pin
IntL is an output pin. When “Low”, it indicates a possible module operational fault or a status critical to the host system. The host identifies the source of the interrupt by using the 2-wire serial interface. The IntL pin is an open collector output and must be pulled up to Vcc on the host board.
Power Supply Filtering
The host board should use the power supply filtering shown in Figure 1.


Figure1. Host Board Power Supply Filtering
Optical Interface Lanes and Assignment
The optical interface port is a male MPO connector .The four fiber positions on the left as shown in Figure 2, with the key up, are used for the optical transmit signals (Channel 1 through4). The fiber positions on the right are used for the optical receive signals (Channel 4 through 1). The central four fibers are physically present.

Figure 2. Optical Receptacle and Channel Orientation
Diagnostic Monitoring Interface
Digital diagnostics monitoring function is available on all HUIHONGFIBER QSFP28 SR4. A 2-wire serial interface provides user to contact with module. The structure of the memory is shown in Figure 3. The memory space is arranged into a lower, single page, address space of 128 bytes and multiple upper address space pages. This structure


permits timely access to addresses in the lower page, such as Interrupt Flags and Monitors. Less time critical time entries, such as serial ID information and threshold settings, are available with the Page Select function. The interface address used is A0xh and is mainly used for time critical data like interrupt handling in order to enable a one-time-read for all data related to an interrupt situation. After an interrupt, IntL, has been asserted, the host can read out the flag field to determine the affected channel and type of flag.

Temperature monitor absolute errorDMI_Temp-3+3degCOver operating temp
Supply voltage monitor absolute errorDMI _VCC-0.10.1VFull operating range
Channel RX power monitor absolute errorDMI_RX-33dBPer channel
Channel Bias current monitorDMI_Ibias-10%10%mAPer channel

Figure 3

EEPROM Serial ID Memory Contents:

Serial ID: Data Fields (Page 00)



NameDescription of Base ID




1281IdentifierIdentifier Type of serial ModuleR


Extended Identifier of Serial ModuleR
1301ConnectorCode for connector typeR
131-1388Specification complianceCode for electronic compatibility or optical compatibilityR
1391EncodingCode for serial encoding algorithmR
1401BR, nominalNominal bit rate, units of 100 MBits/sR
1411Extended rateselect ComplianceTags for extended rate select complianceR
1421Length(SMF)Link length supported for SMF fiber in km (note 1)R
1431Length(OM3 50 um)Link length supported for EBW 50/125 um fiber (OM3), units of 2m (note 1)R


1441Length(OM2 50 um)Link length supported for 50/125 um fiber (OM2), units of 1m (note 1)R

62.5 um)

Link length 62.5/125 um units of 1msupported for fiber (OM1), (note 1)R
1461Length (Copper)Link length of copper or active cable, units of 1 m (note 1)Link length supported for 50/125 um fiber (OM4), units of 2 m) when Byte 147 declares 850 nm VCSEL as defined in

Table 37

1471Device techDevice technologyR
148-16316Vendor nameQSFP28 vendor name(ASCII)R
1641Extended ModuleExtended Module codes for InfiniBandR
165-1673Vendor OUIQSFP28 vendor IEEE company IDR
168-18316Huihongfiber PNPart number provided by QSFP28 vendor(ASCII)R
184-1852Vendor revRevision level for part number provided by vendor(ASCII)R
186-1872Wave length or Copper cable AttenuationNominal laser wavelength (wavelength=value/20 in nm) or copper cable attenuation in dB at 2.5GHz (Adrs 186)and

5.0GHz (Adrs 187)

188-1892Wavelength toleranceGuaranteed range of laser wavelength(+/- value) from


wavelength.(wavelength Tol.=value/200 in nm)

1901Max case temp.Maximum case temperature in degrees CR
1911CC_BASECheck code for base ID fields (addresses 128-190)R
192-1954OptionsRate Select, TX Disable, TX Fault, LOS, Warning indicators for: Temperature, VCC, RX power, TX BiasR
196-21116Vendor SNSerial number provided by vendor (ASCII)R
212-2198Date CodeVendor’s manufacturing date codeR



Indicates which types of diagnostic monitoring are implemented (if any) in the Module. Bit 1,0


2211Enhanced OptionsIndicates which optional enhanced features are implemented in the Module.R


2231CC_EXTCheck code for the Extended ID Fields

(addresses 192-222)

Vendor Specific ID Fields
224-255 32       Vendor Specific EEPROM

Mechanical Dimensions
This transceiver is specified as ESD threshold 1KV for high speed data pins and 2KV for all others    electrical      input      pins,      tested    per       MIL-STD-883,      Method 3015.4 /JESD22-A114-A (HBM).     However, normal ESD precautions are still required during the handling of this module. This transceiver is shipped in ESD protective packaging. It should be removed from the packaging and handled only in an ESD protected environment.
Laser Safety
This is a Class 1 Laser Product according to IEC 60825-1:2007. This product complies with 21 CFR 1040.10 and 1040.11 except for deviations pursuant to Laser Notice No. 50, dated (June 24, 2007)