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What do Ethernet magnetics do?
The magnetics allow different nodes on the Ethernet network to connect over long distances. It removes any connection issues created by different ground offsets at different nodes. The turns ratio on the coils is typically 1:1. The RJ45 connector is a standard connector format for Ethernet link.
Ethernet physical layer
| A standard 8P8C (often called RJ45) connector used most commonly on category 5 cable, one of the types of cabling used in Ethernet networks | |
|---|---|
| Standard | IEEE 802.3 (1983 onwards) |
| Physical media | Coaxial cable, twisted pair, optical fiber |
| Network topology | Point-to-point, star, bus |
Does Ethernet use analog or digital?
Inside an ethernet cable are various copper wires that are used to transmit data and information between the two devices by using analog/digital signals. These cables are used to connect multiple devices and creating or connecting devices to both Local Area Networks (LAN) and Wide Area Networks (WAN).
What is an Ethernet transceiver?
An Ethernet transceiver is a hardware device designed to connect computers or electronic devices within a network, allowing them to transmit and receive messages. A transceiver consists of a transmitter and a receiver, hence the name. An Ethernet transceiver is also known as a media access unit (MAU).
What do you need to know about Ethernet Magnetics?
The properties that Ethernet magnetics need to have are specified in the standard – for example, a transformer for a 100BASE-T connection is required to have an inductance value of at least 350µH when a DC bias of 8mA is applied. Since these attributes are fixed, it may seem like Ethernet magnetics components are all the same.
What kind of transformers are used for Ethernet Magnetics?
TDK has a slightly unusual take on transformers for Ethernet magnetics. The company wanted to use toroidal (doughnut-shaped) transformers in this application as they have excellent leakage flux characteristics, but since toroidal transformers have to be hand-wound, the manufacturing tolerances are typically too loose.
What should I look for in an Ethernet transformer?
First, have a look at the common mode rejection figures, which indicate the modules’ ability to filter out EMI from the received signals. Some Ethernet transformer modules also include a common mode choke for additional filtering, which may be desirable.
What is the inductance value of an Ethernet transformer?
For example, a transformer for a 100BASE-T connection is required to have an inductance value of at least 350µH when a DC bias of 8mA is applied. So all magnetics modules designed for Ethernet isolation will have this in common.