Alpha Bridge ASF28-F-30-AK
Features
- Transmission data rate up to 25.78Gbps
- 850nm VCSEL laser
- PIN photo-detector
- Internal CDR on both transmitter and receiver channels
- Hot-pluggable SFP28 form factor
- Up to 70m on OM3 MMF and 100m on OM4 MMF
- Digital diagnostics functions are available (optional)
- Operating case temperature range 0°C to +70°C
- 3V power supply voltage
- RoHS-6 compliant
Applications
- IEEE 802.3by 25GBASE-SR
Absolute Maximum Ratings
| Parameter | Symbol | Min. | Max. | Units | Note |
| Supply Voltage | Vcc | 0 | 3.6 | V | |
| Storage Temperature | TS | -40 | 85 | °C | |
| Case Operating Temperature | Tc | 0 | 70 | °C | |
| Relative Humidity | RH | 5 | 85 | % | 1 |
Recommended Operating Conditions
| Parameter | Symbol | Min. | Typical | Max. | Units | Note |
| Supply Voltage | Vcc | 3.13 | 3.3 | 3.47 | V | |
| Supply Current | Icc | 300 | mA | |||
| Fiber Length on 50/125μm high-bandwidth (OM3) MMF | 70 | m | ||||
| Fiber Length on 50/125μm high-bandwidth (OM4) MMF | 100 | m |
Diagnostics Specification
| Parameter | Range | Units | Accuracy | Calibration |
| Temperature | 0 to +70 | °C | ±3°C | Internal / External |
| Voltage | 3.0 to 3.6 | V | ±3% | Internal / External |
| Bias Current | 0 to 20 | mA | ±10% | Internal / External |
| TX Power | -8 to 3 | dBm | ±3dB | Internal / External |
| RX Power | -14 to 0 | dBm | ±3dB | Internal / External |
Transmitter Electro-optical Characteristics
| Parameter | Symbol | Min | Type | Max | Units | Notes |
| Data Rate | BR | 25.78 | Gbps | |||
| Centre Wavelength | λc | 840 | 1310 | 860 | nm | |
| Spectral Width (-20dB) | σ | 0.6 | nm | |||
| Average Output Power | Pavg | -8.4 | 2.4 | dB | ||
| Optical Power OMA | POMA | -6.4 | 3 | dBm | ||
| Extinction Ratio | ER | 2 | dB | |||
| Differential data input swing | VIN,PP | 40 | 1000 | mV | ||
| Input Differential Impedance | ZIN | 90 | 100 | 110 | Ω | |
| TX Disable | Disable | 2.0 | Vcc | V | ||
| Enable | 0 | 0.8 | V | |||
| TX Fault | Fault | 2.0 | Vcc | V | ||
| Normal | 0 | 0.8 | V |
Transmitter Electro-optical Characteristics
| Parameter | Symbol | Min | Type | Max | Units | Notes |
| Data Rate | BR | 25.78 | Gbps | |||
| Centre Wavelength | λc | 840 | 1310 | 860 | nm | |
| Spectral Width (-20dB) | σ | 0.6 | nm | |||
| Average Output Power | Pavg | -8.4 | 2.4 | dB | ||
| Optical Power OMA | POMA | -6.4 | 3 | dBm | ||
| Extinction Ratio | ER | 2 | dB | |||
| Differential data input swing | VIN,PP | 40 | 1000 | mV | ||
| Input Differential Impedance | ZIN | 90 | 100 | 110 | Ω | |
| TX Disable | Disable | 2.0 | Vcc | V | ||
| Enable | 0 | 0.8 | V | |||
| TX Fault | Fault | 2.0 | Vcc | V | ||
| Normal | 0 | 0.8 | V |
Receiver Electro-optical Characteristics
| Parameter | Symbol | Min | Type | Max | Units | Notes |
| Data rate | BR | 25.78 | Gbps | |||
| Centre Wavelength | λc | 840 | 850 | 860 | nm | |
| Receiver Sensitivity (OMA) | Psens | -10 | dBm | |||
| Stressed Sensitivity (OMA) | -5.2 | dBm | ||||
| Receiver Power (OMA) | 3 | dBm | ||||
| LOS De-Assert | LOSD | -13 | dBm | |||
| LOS Assert | LOSA | -30 | dBm | |||
| LOS Hysteresis | 0.5 | dB | ||||
| Differential data output swing | Vout,PP | 300 | 850 | mV | ||
| LOS | High | 2.0 | Vcc | V | ||
| Low | 0.8 | V |
Pin Descriptions
| Pin | Logic | Symbol | Name/Description | Note |
| 1 | VeeT | Module Transmitter Ground | 1 | |
| 2 | LVTTL-O | TX_Fault | Module Transmitter Fault | 2 |
| 3 | LVTTL-I | TX_Dis | Transmitter Disable; Turns off transmitter laser output | |
| 4 | LVTTL-I/O | SDA | 2-Wire Serial Interface Data Line | 2 |
| 5 | LVTTL-I | SCL | 2-Wire Serial Interface Clock | 2 |
| 6 | MOD_ABS | Module Definition, Grounded in the module | ||
| 7 | LVTTL-I | RS0 | Receiver Rate Select | |
| 8 | LVTTL-O | RX_LOS | Receiver Loss of Signal Indication Active LOW | |
| 9 | LVTTL-I | RS1 | Transmitter Rate Select (not used) | |
| 10 | VeeR | Module Receiver Ground | 1 | |
| 11 | VeeR | Module Receiver Ground | 1 | |
| 12 | CML-O | RD- | Receiver Inverted Data Output | |
| 13 | CML-O | RD+ | Receiver Data Output | |
| 14 | VeeR | Module Receiver Ground | 1 | |
| 15 | VccR | Module Receiver 3.3 V Supply | ||
| 16 | VccT | Module Receiver 3.3 V Supply | ||
| 17 | VeeT | Module Transmitter Ground | 1 | |
| 18 | CML-I | TD+ | Transmitter Non-Inverted Data Input | |
| 19 | CML-I | TD- | Transmitter Inverted Data Input | |
| 20 | VeeT | Module Transmitter Ground | 1 |
Ordering Information
| Part Number | Model Number | Length (M) | Voltage | Temperature |
| ASF28-F-30-AK | Active Optical Cable | 30 | 3.3V | 0°C to 70 °C |

