Specifications

ASIX ELECTRONICS CORPORATION
4
AX88772
USB to 10/100 Fast Ethernet/HomePNA Controller
1.0 Introduction
1.1 General Description
The AX88772 USB to 10/100 Fast Ethernet/HomePNA/HomePlug controller is a high performance and highly integrated
ASIC with embedded 28KB SRAM for packet buffering. It enables low cost and affordable Fast Ethernet network
connection to desktop, notebook PC, and embedded system using popular USB ports. It has an USB interface to
communicate with USB host controller and is compliant with USB specification V1.1 and V2.0. It implements
10/100Mbps Ethernet LAN function based on IEEE802.3, and IEEE802.3u standards or HomePNA standard. It
integrates an on-chip 10/100Mbps Ethernet PHY to simplify system design and provides an optional media-independent
interface (MII) for implementing Fast Ethernet and HomePNA functions.
The AX88772 needs 12MHz clock for USB operation and 25Mhz clock for Fast Ethernet operation. It is in 128-pin LQFP
low profile package with CMOS process and requires only single 3.3V power supply to operate.
1.2 AX88772 Block Diagram
Figure 1: AX88772 Block Diagram
RXIP/RXIN
TXOP/TXON
MII I/F
GPIO2~0
MAC
Core
Memory Arbiter
USB to
Ethernet
Bridge
USB Core and Interface
STA
SEEPROM
Loader I/F
DP/DM
DPRS/DMRS
MDC
MDIO
EECS
EECK
EEDI
EEDO
28KB
SRAM
General
Pur
p
ose I/O
10/100
Ethernet
PHY