GENERAL DESCRIPTION
Realtek patented removal of traditional SD pins in 100Base-FX (RTL8208BF-LF only) allow us to obtain a lower pincount. Flexible hardware settings are provided to configure the various operating modes of the chip. Each channel consists of an RMII/SMII/SS-SMII interface-to-MAC controller, and hardware pins are used to configure the interface for RMII, SMII, or SS-SMII mode. In RMII mode, another hardware pin is used to set Port-Pair Loopback mode (PP-LPBK MODE, RTL8208BF-LF only), which can extend physical transmission length and perform physical media transport operations without a switch controller. A PECL (Pseudo Emitter Coupled Logic) receiver accepts input from a fiber transceiver and directly passed to a clock recovery circuit for data/clock recovery. The chip utilizes an advanced CMOS process to meet low voltage and low power requirements. With on-chip DSP (Digital Signal Processing) technology, the chip provides excellent performance under all operating conditions.