Overview of SFP optical modules

January 8, 2020

The SFP optical module is a hot plug small package module encapsulated by SFP. The current maximum rate is 10.3 G and the interface is LC. SFP optical modules are mainly composed of lasers. SFP classification can be divided into rate classification, wavelength classification, and pattern classification. The SFP light module consists of a laser(including a transmitter TOSA and a receiver ROSA) and a circuit board IC and external accessories. The external accessories consist of a shell, a base, a PCBA, a pull ring, a clasp, a unlock piece, and a rubber plug. For ease of identification, the type of parameter of the module is generally identified by the color of the pull ring.

Classification of SFP

1. Rate classification
According to the rate, 155M/622M/1 .25 G/2 .125 G/4 .25 G/8G/10 G, 155M and 1.25 G are more used in the market, 10G technology is gradually maturing, and demand is developing in an increasing manner.

2. Wavelength classification
According to the wavelength of 850nm / 1310nm / 1550nm / 1490nm / 1530nm / 1610nm, the wavelength of 850nm is SFP multimode, the transmission distance is below 2KM, the wavelength is 1310/1550nm is a single mode, and the transmission distance is above 2KM. Relatively speaking, these three wavelengths are cheaper than the other three.
If the naked module is not identified, it is easy to confuse. General manufacturers will distinguish between the colors of the pull rings. For example, the black pull rings are multimode and the wavelength is 850 nm; Blue is a module with a wavelength of 1310 nm; Yellow is a module with a wavelength of 1550 nm; Purple is a module with a wavelength of 1490 nm.

3. Pattern classification
Almost all multimode fiber sizes are 50/125um or 62.5 / 125um, and the bandwidth(the amount of information transmitted by the fiber) is usually 200 MHz to 2 GHz. The multimode optical terminal machine can transmit up to 5 kilometers through multimode fiber. Using a light emitting diode or laser as a light source. The pull ring or external color is black.


Single mode
The single-mode fiber is 9-10 / 125 μm in size and has unlimited bandwidth and lower loss than the multi-mode fiber. Single-mode optical terminals are mostly used for long-distance transmission, sometimes reaching 150 to 200 kilometers. LD or LED with narrow spectral lines is used as a light source. The pull ring or external color is blue, yellow or purple.


Distinction and linkages
Single mode fiber is cheap, but single mode devices are much more expensive than similar multimode devices. Single-mode devices can usually operate on both single-mode fiber and multi-mode fiber, while multi-mode devices are limited to operating on multi-mode fiber.
The 10G module experienced the development of 300Pin, XENPAK, X2, and XFP, and eventually achieved the transmission of 10G signals in the same size as SFP. This is SFP +. SFP has satisfied the demand for high-density optical modules with its miniaturization and low-cost advantages. It has been pushed from the 2002 standard and has replaced XFP as the mainstream of the 10G market by 2010.

SHENZHEN OPTFOCUS TECHNOLOGY is located in Shenzhen's scientific research base, Shenzhen University City. It brings together a group of young people with professional knowledge and is rooted in Shenzhen. It focuses on the research and development of optical fiber transmission technology products and seeks to bring SHENZHEN OPTFOCUS products have become a well-known brand in China. Its products include optical fiber transceivers, EPON systems, Ethernet switches, EOC, POE switches, optical fiber switches, industrial Ethernet switches, CWDM, video optical terminals and other optical fiber transmission access devices.