RTL8208B-LF/RTL8208BF-LF
Datasheet
1. General Description
The RTL8208B-LF and RTL8208BF-LF (jointly referred to as the RTL8208B(F)-LF) are single-chip
highly integrated 8-port, 10Base-T/100Base-TX (FX) Ethernet transceivers implemented in 0.18µm
CMOS technology. They are currently the world’s smallest Octal-PHY chip package. Realtek patented
removal of traditional SD pins in 100Base-FX (RTL8208BF-LF only) allow us to obtain a lower pin-
count. Flexible hardware settings are provided to configure the various operating modes of the chip.
The RTL8208B(F)-LF provides 8 separate and independent channels. 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.
A built-in UTP cable tester diagnoses an open/short fault in an attached cable. The RTL8208B(F)-LF also
features very low power consumption (maximum of 1.6W). Additionally, pin-outs are designed to
provide optimized direct routing, which simplifies the layout work and reduces EMI noise issues.
Single-Chip Octal 10/100-TX/FX PHY Transceiver
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Track ID: JATR-1076-21 Rev. 1.3
REALTEK [ Realtek Semiconductor Corp. ]
