2120C
The 78Q2120C is a form, fit and function replacement for the popular 78Q2120-64CGT 10BASE-T/100BASE-TX Fast Ethernet transceiver. It includes integrated MII, ENDECs, scrambler/descrambler, dual-speed clock recovery, and full-featured auto-negotiation functions. The transmitter includes an on-chip pulse-shaper and a low-power line driver. The receiver has an adaptive equalizer and a baseline restoration circuit required for accurate clock and data recovery. The transceiver interfaces to Category-5 unshielded twisted pair (Cat-5 UTP) cabling for 100BASE-TX/10BASE-T and Category-3 unshielded twisted pair for 10BASE-T, and is connected to the line media via 1:1 isolation transformers. No external filter is required.Features
10BASE-T/100BASE-TX IEEE-802.3 compliant PHYFull duplex operation with Auto Negotiation
PCS Bypass supports 5-bit symbol interface
Register-programmable transmit amplitude
Dual speed digital clock recovery, auto polarity correction
