AM79C875中文资料超威半导体数据手册PDF规格书

GENERAL DESCRIPTION

The NetPHY™ 4LP device is a highly integrated, low power 10BASE-T/100BASE-TX/FX Quad Ethernet transceiver. The NetPHY™ 4LP device includes integrated RMII, ENDECs, Scrambler/Descrambler, and full-featured Auto-Negotiation with support for Parallel Detection and Next Page. Port 3 can be configured as a 100BASE-FX transmitter to output an NRZI PECL level signal. Each receiver has an adaptive equalizer/DC restoration circuit for accurate clock/data recovery on the 100BASE-TX signal at different cable lengths and can perform to 125 m and beyond.

DISTINCTIVE CHARACTERISTICS

■ Four 10/100BASE-TX Ethernet PHY transceivers

■ Supports RMII (Reduced MII) interface

■ 125 meter (m) MLT-3 and Baseline Wander operation

■ Low power consumption

— 1.3 Watt (W) typical (1:1 magnetics)

— 1.2 W typical (1.25:1 magnetics)

■ Power management modes:

— Selectable 1:1 or 1.25:1 transmit transformer

— Unplugged - approximately 100 mW per port

— Power Down - approximately 3 mW per port

■ Single 3.3 V power supply with 5 V I/O tolerance

■ Patent-pending DC restoration technique reduces baseline wander susceptibility

■ Full and half-duplex operation with full-featured Auto-Negotiation function

■ Next Page register support

■ Automatic Polarity Detection during AutoNegotiation and 10BASE-T signal reception

■ Unique scramble seed per port reduces EMI in switch and repeater applications

■ One port supports 100BASE-FX function

■ Supports Inter Packet Gap as low as 40 ns for high throughput applications

■ No external filters or chokes required

■ Compliant with IEEE 802.3 standards for 100BASE-TX, 100BASE-FX, and 10BASE-T

■ Built-in loopback and test modes

■ Small 14 x 20 mm 100-pin PQR package

■ Small package allows side-by-side PHY layout

— Fits neatly behind quad magnetics

— Saves board space over larger 208 PQFP packages

■ Support for Industrial Temperature (-40°C to +85°C)