Transceivers Come In Two Styles

Expanding its packaging options for 10BaseT/100BaseTX fast Ethernet transceivers, the 78Q2120-64 comes in a 64-pin QFP as well as the original 80-pin TQFP. The 78Q2120-64 is a low-cost, high-profile 3.3V or 5V solution targeted for desktop network interface cards. This single-chip, mixed-signal physical layer transceiver with full on-chip auto-negotiation accommodates fast Ethernet data streams over standard Category 5 unshielded-twisted-pair (UTP) cables and interfaces to the controller via the standard media independent interface (MII). The transceiver requires a simple 1:1 isolation transformer, a 25-MHz crystal and an industry-standard media access controller chip to implement an Ethernet network adaptor.