1m Cisco Qsfp-4SFP25g-Cu50cm Compatible 100g Qsfp28 to 4 X 25g SFP28 Direct Attach Breakout Cable Dac, #C0028
Guangdong, China
Last Login Date:
Jul 28, 2025
Main Products:
PLC Splitter, Fiber Optic Patch Cord, MPO Cable Assembly, MPO Cable, Aoc, Fiber Optic Transceiver, Fbg Sensor, Ceramic Ferrule, Wdm, Mt Ferrule
Product Description
Company Info
Basic Info.
Product Description
QSFP28 Direct Attach Cables are compliant with the SFF-8665 specifications. SFP28 Direct Attach Cables are compliant with SFF-8432 and SFF-8402 specifications. Various choices of wire gauge are available from 30 to 26 AWG with various choices of cable length (up to 5m).
Up to 25.78Gbps data rate per channel
Up to 5m transmission
Hot-pluggable QSFP+ 38 PIN footprint
Compatible to SFF-8665
Compliant with IEEE 802.3bj
Single 3.3V power supply
Temperature Range: 0 °C to 70 °C
RoHS compliant
Low EMI radiation switches, servers and routers
Data center networks
Storage area networks
High performance computing
Telecommunication and wireless infrastructure
Medical diagnostics and networking
Test and measurement equipment
Recommended Operation Condition
| Parameter | Symbol | Min | Max | Unit |
| Operating Case Temperature | Topc | 0 | 70 | degC |
| Storage Temperature | Tst | -40 | 85 | degC |
| Relative Humidity (non-condensation) | RS | 35 | 60 | % |
| Supply Voltage | VCC3 | 3.135 | 3.465 | V |
| Voltage on LVTTL Input | Vilvttl | -0.3 | VCC3 +0.2 | V |
| Power Supply Current | ICC3 | - | 15 | mA |
| Total Power Consumption | Pd | - | 0.05 | W |
Stress or conditions exceed the above range may cause permanent damage to the device.
This is a stress rating only and functional operation of the device at these or any other conditions above those listed in the operational sections of this specification is not applied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Frequency Domain
| Item | Test Parameter | IEEE802.3bj Specification |
| 1 | Differential Insertion Loss (SDD12) | Maximum insertion loss at 12.8906Ghz @22.48dB Minimum insertion loss at 12.8906Ghz@8dB |
| 2 | Differential Insertion Loss (SDD21) | Maximum insertion loss at 12.8906Ghz@22.48dB Minimum insertion loss at 12.8906Ghz@8dB |
| 3 | Differential Return Loss (SDD22) | -16.5+2xSQRT(f) @ 0.01 to 4.1GHz -10.66+14xlog10f/5.5@4.1 to 19GHz |
| 4 | Differential Return Loss (SDD11) | -16.5+2xSQRT(f) @ 0.01 to 4.1GHz -10.66+14xlog10f/5.5@4.1 to 19GHz |
| 5 | Common Mode Reflection (SCC22) | -2dB @ 0.01 to 19GHz |
| 6 | Common Mode Reflection (SCC11) | -2dB @ 0.01 to 19GHz |
| 7 | Common Mode Conversion (SCD22) | -22+(20/25.78)*(f) @ 0.01 to 12.89GHz -15+(6/25.78)*(f) @ 12.9 to 19GHz |
| 8 | Common Mode Conversion (SCD11) | -22+(20/25.78)*(f) @ 0.01 to 12.89GHz -15+(6/25.78)*(f) @ 12.9 to 19GHz |
| 9 | Differential to Common Mode Conversion Loss (SCD12) | -10dB @ 0.01 to 12.89GHz -27+(29/22)*(f) @ 12.9 to 15.7GHz -6.3dB @ 15.71 to 19GHz |
| 10 | Differential to Common Mode Conversion Loss (SCD21) | -10dB @ 0.01 to 12.89GHz -27+(29/22)*(f) @ 12.9 to 15.7GHz -6.3dB @ 15.71 to 19GHz |
QSFP28 Pin Definition
| Pin | Symbol | Name/Description |
| 1 | GND | Ground |
| 2 | Tx2n | Transmitter Inverted Data Input |
| 3 | Tx2p | Transmitter Non-Inverted Data Input |
| 4 | GND | Ground |
| 5 | Tx4n | Transmitter Inverted Data Input |
| 6 | Tx4p | Transmitter Non-Inverted Data Input |
| 7 | GND | Ground |
| 8 | ModSelL | Module Select |
| 9 | ResetL | Module Reset |
| 10 | Vcc Rx | +3.3 V Power supply receiver |
| 11 | SCL | 2-wire serial interface clock |
| 12 | SDA | 2-wire serial interface data |
| 13 | GND | Ground |
| 14 | Rx3p | Receiver Non-Inverted Data Output |
| 15 | Rx3n | Receiver Inverted Data Output |
| 16 | GND | Ground |
| 17 | Rx1p | Receiver Non-Inverted Data Output |
| 18 | Rx1n | Receiver Inverted Data Output |
| 19 | GND | Ground |
| 20 | GND | Ground |
| 21 | Rx2n | Receiver Inverted Data Output |
| 22 | Rx2p | Receiver Non-Inverted Data Output |
| 23 | GND | Ground |
| 24 | Rx4n | Receiver Inverted Data Output |
| 25 | Rx4p | Receiver Non-Inverted Data Output |
| 26 | GND | Ground |
| 27 | ModPrsL | Module Present |
| 28 | IntL | Interrupt |
| 29 | Vcc Tx | +3.3 V Power supply transmitter |
| 30 | Vcc1 | +3.3 V Power Supply |
| 31 | LPMode | Low Power Mode |
| 32 | GND | Ground |
| 33 | Tx3p | Transmitter Non-Inverted Data Input |
| 34 | Tx3n | Transmitter Inverted Data Input |
| 35 | GND | Ground |
| 36 | Tx1p | Transmitter Non-Inverted Data Input |
| 37 | Tx1n | Transmitter Inverted Data Input |
| 38 | GND | Ground |
Sfp28 Pin Descriptions
| Pin | Symbol | Name/Description |
| 1 | VEET [1] | Transmitter Ground |
| 2 | Tx_FAULT [2] | Not used |
| 3 | Tx_DIS [3] | Not used |
| 4 | SDA [2] | 2-wire Serial Interface Data Line |
| 5 | SCL [2] | 2-wire Serial Interface Clock Line |
| 6 | MOD_ABS [4] | Module Absent. Grounded within the module |
| 7 | RS0 [5] | Not used |
| 8 | RX_LOS [2] | Loss of Signal indication. Logic 0 indicates normal operation |
| 9 | RS1 [5] | Not used |
| 10 | VEER [1] | Receiver Ground |
| 11 | VEER [1] | Receiver Ground |
| 12 | RD- | Receiver Inverted DATA out. AC Coupled |
| 13 | RD+ | Receiver DATA out. AC Coupled |
| 14 | VEER [1] | Receiver Ground |
| 15 | VCCR | Receiver Power Supply |
| 16 | VCCT | Transmitter Power Supply |
| 17 | VEET [1] | Transmitter Ground |
| 18 | TD+ | Transmitter DATA in. AC Coupled |
| 19 | TD- | Transmitter Inverted DATA in. AC Coupled |
| 20 | VEET [1] | Transmitter Ground |
Notes:
1. Module circuit ground is isolated from module chassis ground within the module.
2. should be pulled up with 4.7k - 10k ohms on host board to a voltage between 3.15Vand 3.6V.
3. Tx_Disable is an input contact with a 4.7 kΩ to 10 kΩ pullup to VccT inside the module.
4. Mod_ABS is connected to VeeT or VeeR in the SFP+ module. The host may pull this contact up to Vcc_Host with a resistor in the range 4.7 kΩ to10 kΩ.Mod_ABS is asserted "High" when the SFP+ module is physically absent from a host slot.
5. RS0 and RS1 are module inputs and are pulled low to VeeT with > 30 kΩ resistors in the module.
Please visit T&S Communications Co., Ltd. website for more information.
