What is the difference between SFP+ and SFP
The difference between SFP+ and SFP. The pinout of SFP and SFP+ connectors are identical. However, SFP is data rate of 6Gb/s, whereas SFP+ is designed for 10Gb/s.
The SFP receptacles and plugs are not as well impedance matched as SFP+ receptacles and plugs.
Also SFP+ cable is designed for 10Gb/s whereas SFP cable may not be able to satisfactorily transmit that rate.
1. Visual Method: Check the faulty module appearance. Whether there is obvious damage, component burned black, dehiscence, leakage, even tin or not.2. Comparative Law: Use certain tools and a good module. Test the good module and the target module. Mainly analyze circuit parts or components' resistance, voltage, waveform, etc. Then make a comparison.3. Substitution Method: To replace the components of the module; then to analyze the change of operating parameters. 4. Others
A. Optical power badness performance A1. BIAS optical bias current within the normal range, the optical power exceeds out of the control range. A2. Laser bias current of BIAS in the normal range, the optical power is less than the control range. A3. There is no light. A3.a. BIAS value is displayed as 0. A3.b. BIAS short circuit, value is very great, displayed as 90mA ~ 150mA; and data can be saved. A4. There is light during the debug process, but the optical power don't change A5. Optical power is unstable. A6. Side mode suppression ratio is small. B. Eye diagram badness performance B1. Extinction ratio of non-performing B1.a Small extinction ratio B1.b Large extinction ratio B2. Eye
A1.1 Emission component TOSA is bad. Maintenance method is to replace the TOSA.A1.2 The TOSA PINs PD+ is welded badly so that the power is so large. But when debug the software, the power won’t be changed. Maintenance method is to weld the pin better.A1.3 Power and resistance don't match with the BIAS optical bias current. Maintenance method is to improve the power and resistance. A2.1 Emission component TOSA is bad. The maintenance method is to replace the TOSA.A2.2 Paste is bad or poor performance of driver chip. The repair method is to re-paste driver chip or to replace the chip.A2.3 Power and resistance don't match with the BIAS optical bias current. Maintenance method is to reduce