The ML6651 converts signals transmitted between twisted pair and fiber optic Ethernet technologies. It supports conversion between 10BASE-T and 10BASE-FL, between 100BASE-TX and 100BASE-FX/SX, and between FLP (fast link pulse) bursts and FLNP (fiber link negotiation pulse) bursts. Either 850nm or 1300nm laser optics can be used for both 10 and 100 Mb/second operating data rates while fully auto-negotiating for speed and duplex mode communication. One or both of the fiber optic and twisted pair interfaces can be set to interface with industry standard 1x9 fiber optic PMD modules, using PECL or LVPECL compatible modes.