The 84225 is a highly integrated Ethernet transceiver for twisted pair and fiber Ethernet applications. The 84225 can be configured for either 100 Mbps (100BaseFX or 100BaseTX) or 10 Mbps (10BaseT) Ethernet operation. The 84225 consists of four (4) separate and independent channels. Each channel consists of: 4B5B/Manchester encoder, scrambler, transmitter with wave shaping and on-chip filters, transmit output driver, receiver with adaptive equalizer, filters, baseline wander correction, clock and data recovery, descrambler, 4B5B/Manchester decoder, and controller interface (MII or RMII). The addition of internal output waveshaping circuitry and on-chip filters eliminates the need for external filters normally required in 100BaseTX and 10BaseT.
The 84225 is a highly integrated Ethernet transceiver that provides four independent channels for 100BaseTX, 100BaseFX, and 10BaseT applications. It includes on‑chip wave shaping, adaptive equalization, and baseline wander correction, eliminating the need for external filters.
The document covers pin descriptions for power, media, controller, management, and LED interfaces, as well as configuration registers, LED behavior, and revision history. It is intended for designers of switching hubs, repeaters, routers, bridges, and other multi‑port Ethernet equipment.
| Number of independent channels | 4 |
|---|---|
| Supported media types | 100BaseTX, 100BaseFX, 10BaseT |
| Power supply voltage | +3.3 V +/-5% |
| I/O voltage tolerance | 5 V tolerant |
| Maximum data rate | 100 Mbps |
| Package type | W160L PQFP (160‑pin) |
| LED functions | Link, Activity, Collision, Full Duplex, 10 Mbps Link Detect |
It uses a +3.3 V supply with a tolerance of +/-5 %.
The device contains four independent channels.
It complies with IEEE 802.3 standards for 10BaseT, 100BaseTX and 100BaseFX.
The LEDDEF pin selects the default LED functions such as LINK+ACT, COL, FDX, etc.