Description
| Optical transmitter Characteristics | ||||||
| Parameter | Symbol | Min | Typical | Max | Unit | Notes |
| Launched Power (avg.) | POUT | -8.4 | 2.4 | dBm | ||
| Optical Power OMA | POMA | -6.4 | 3 | dBm | ||
| Operating Wavelength
Range |
λC | 840 | 850 | 860 | nm | |
| Spectral Width (RMS) | ∆λ | 0.6 | nm | |||
| Extinction Ratio | ER | 2 | dB | |||
| Transmitter and Dispersion
Penalty |
TDP | 4.3 | dB | |||
| Optical Output Power after
TX Disable |
PDIS | -30 | dBm | |||
| Relative Intensity Noise | RIN | -128 | dB/Hz | |||
| Optical Return Loss
Tolerance |
ORL | 12 | dB | |||
| Optical Receiver Characteristics | ||||||
| Parameter | Symbol | Min | Typical | Max | Unit | Notes |
| Wavelength Range | λC | 840 | 850 | 860 | nm | |
| Average Receiver Power | Pmax | -10.3 | 2.4 | dBm | ||
| Receiver Sensitivity
(Average power) |
Psen |
-10.3 |
dBm | 1,2 | ||
| LOS De-Assert | LOSD | -13 | dBm | |||
| LOS Assert | LOSA | -30 | dBm | |||
| LOS Hysteresis | 0.5 | dB | ||||
| Receiver Reflectance | Rr | -12 | dB | |||
Notes:
1.Measured with a PRBS 231-1 test pattern, @25.78125Gb/s, BER<5E-5.
2.Minimum value is informative, equals min Tx OMA with infinite ER and max channel insertion loss.
The SFP28 modules are hot-pluggable. Hot pluggable refers to plugging in or unplugging a module while the host board is powered. The SFP28 host connector is a 0.8 mm pitch 20 position right angle improved connector specified by SFF-8431, or stacked connector with equivalent electrical performance. SFP28 module contacts mates with the host in the order of ground, power, followed by signal as illustrated by Figure 1 and the contact sequence order listed in Table 1.
Figure 1 SFP28 Pad Assignment Top View
| Pin
No |
Symbol | Name/Description | Power Seq. | Note |
| 1 | VeeT | Transmitter Ground | 1st | 1 |
| 2 | TX_Fault | Transmitter Fault | 3rd | 2 |
| 3 | TX_Disable | Transmitter Disable | 3rd | 3 |
| 4 | SDA | 2-Wire Serial Interface Data Line | 3rd | 4 |
| 5 | SCL | 2-Wire Serial Interface Data Line | 3rd | 4 |
| 6 | Mod_ABS | Module Absent, Connect to VeeT or VeeR in Module | 3rd | 5 |
| 7 | RS0 | No connection required | 3rd | 6 |
| 8 | RX_LOS | Receiver Loss of Signal indication | 3rd | 7 |
| 9 | RS1 | No connection required | 3rd | 8 |
| 10 | VeeR | Receiver Ground | 1st | 1 |
| 11 | VeeR | Receiver Ground | 1st | 1 |
| 12 | RD- | Receiver Inverted DATA out. AC Coupled. CML-O | 3rd | 9 |
| 13 | RD+ | Receiver Non-inverted DATA out. AC Coupled. CML-O | 3rd | 9 |
| 14 | VeeR | Receiver Ground | 1st | 1 |
| 15 | VccR | Receiver Power Supply | 2nd | 10 |
| 16 | VccT | Transmitter Power Supply | 2nd | 10 |
| 17 | VeeT | Transmitter Ground | 1st | 1 |
| 18 | TD+ | Transmitter Non-Inverted DATA in. AC Coupled. CML-I | 3rd | 11 |
| 19 | TD- | Transmitter Inverted DATA in. AC Coupled. CML-I | 3rd | 11 |
| 20 | VeeT | Transmitter Ground | 1st | 1 |
Power Seq.: Pin engagement sequence during hot plugging.
Notes:
1.The module signal ground contacts.
2.This pin is an open drain/collector and should be pulled up to Vcc-host in the host with a 4.7k~10k Ohm resistor.
3.This pin should be pulled up to VccT with a 4.7k~10k Ohm resistor in modules.
4.SDA&SCL (IIC) are needed pull up 4.7k~10k Ohm resistors on host board.
5.Mod_ABS is connected to VeeT or VeeR in the SFP28 module.
6.Rate Select 0, no connection required.
7.Module RX_Los of signal indication need pull up 4.7k~10k Ohm resistor on host board.
8.Rate Select 1, no connection required.
9.RD -/+: These are the differential receiver outputs. They are CML AC-coupled with 100 Ohm terminal resistor matching internal.
10.VccR and VccT are the receiver and transmitter power supplies.
11.TD-/+: These are the differential transmitter inputs. They are CML AC-coupled with 100 Ohm terminal resistor matching internal
| PART NO. | 产品描述Specifications | |||||||
| Pack | Rate | Tx | Po | Sen | Temp | Reach | DDM | |
| (Gbps) | (nm) | (dBm) | (dBm) | (℃) | (m) | |||
|
HD-SFP28/25G-SR |
SFP28 |
25.78125 |
850 |
-8.4~2.4 |
<-10.3 |
0~70 |
100 |
Y |
*Note：
1.Measured with a PRBS 231-1 test pattern, @25.78125Gb/s, BER<5E-5.
2.OM3 Cable length =<70m or OM4 Cable length =<100m.
3.More detail product selection and cable lengths, please contact xuhong
