Single-Port
LAN Transformer
SMD single-port Ethernet signal transformers — IEEE 802.3 compliant signal isolation for servers, switches, routers and networking equipment, with a complete line from 10BASE-T to 10GBASE-T.
Single-port Ethernet transformers in two packages
From standard Gigabit to Multi-Gig applications, in the 3232 and 4532 SMD package series.
3232 Series
The most compact package, suited to space-constrained networking modules and higher port-density designs, supporting 10/100/1000BASE-T.
4532 Series
The main series, with a wider choice of inductance values, covering 1000BASE-T and 2.5G / 5G / 10GBASE-T Multi-Gig applications.
| Part No. | Size (mm) | Inductance | Insertion Loss | Turn Ratio | Hi‑Pot | Application | Datasheet |
|---|---|---|---|---|---|---|---|
| MAT3232T-151-G1-6L | 3.2 × 3.2 | 150 µH | 2.5 dB @ 0.1–100 MHz | 1CT:1CT | 1500 Vrms | 10/100/1000BASE‑T | |
| MAT4532T-121-G10-6L | 4.5 × 3.2 | 120 µH | 1.5 dB @ 0.1–500 MHz | 1CT:1CT | 1500 Vac | 10GBASE‑T | |
| MAT4532T-181-G5-6L | 4.5 × 3.2 | 180 µH | 1.5 dB @ 0.1–250 MHz | 1CT:1CT | 1500 Vac | 1000 / 2.5G / 5GBASE‑T | |
| MAT4532T-201-G1-6L | 4.5 × 3.2 | 200 µH | 1.5 dB @ 0.1–100 MHz | 1CT:1CT | 1500 Vac | 10/100/1000BASE‑T |
Inductance measured at DC bias 8 mA @ 100 kHz (Min.) · insertion loss and hi-pot are Max. values; measurement bandwidth varies by part number · click a part number for full specifications, or download the datasheet PDF directly.
Moritek
4.5×3.2mm
120 µH
From discrete components to multi-port modules
The discrete single-port design gives customers full layout freedom — mount individual parts on your own board, or integrate them into multi-port LAN magnetics modules.
Module photos illustrate discrete single-port parts integrated into modules; actual specifications and port counts can be customised.
How a single-port transformer sits in an Ethernet circuit
The MAT series is a 6-pin single-port design with one centre-tapped winding on each side (1CT:1CT) — one side faces the PHY / MAC, the other faces the RJ45 connector.
| Pin | Side | Function | Typical connection |
|---|---|---|---|
| 1 | PHY side | Winding end A | To PHY differential TX+ / RX+ |
| 2 | PHY side | Winding end B | To PHY differential TX− / RX− |
| 6 | PHY side | Centre tap (CT) | To PHY-side common-mode voltage / decoupling capacitor |
| 5 | Line side | Winding end A | To RJ45 differential pin |
| 4 | Line side | Winding end B | To RJ45 differential pin |
| 3 | Line side | Centre tap (CT) | To Bob Smith termination / capacitor to ground |
1CT:1CT turn ratio · 1500 V hi-pot (60 s) · four parts per RJ45 port, one for each twisted pair. Always follow the SCHEMATIC DIAGRAM in the individual part datasheet for the actual wiring.
LAN Transformer
The transformer removes any DC path between the PHY and the cable, blocking ground potential differences between the two ends and providing 1500 V of dielectric protection.
Common-mode rejection
Differential transmission with a centre tap cancels noise that appears in phase on both lines, cutting EMI emission and susceptibility to external interference.
Impedance matching
The 1CT:1CT ratio matches the 100 Ω differential impedance of Ethernet, preserving signal integrity and reducing return loss.
PoE compatible
The centre tap serves as the injection point for PoE, letting data and power share the same twisted pairs.
A new generation of SMD single-port transformers
Automated winding with a discrete single-port design — compared with hand-wound toroidal cores and bulky integrated modules, it wins on consistency, layout flexibility and manufacturability.
Automated winding · consistent quality
Automated winding and automated electrode termination give consistent part-to-part characteristics and stable yield, without the wider tolerances of hand-wound toroidal cores.
Discrete single-port · layout freedom
Replacing bulky LAN modules that pack the transformer and common-mode choke together, the discrete approach frees up routing and even allows double-sided placement for higher port density.
Miniaturised · fully SMT
3.2×3.2 and 4.5×3.2 mm SMD packages suit automated SMT lines, saving both board space and assembly cost.
Multi‑Gig Ready
Covering 1000BASE-T to 10GBASE-T for next-generation high-speed networking and PoE applications.