802.11b
Media Access
Controller
(MAC) and
Baseband with
USB Interface
AT76C505A
Summary
Rev. 2389BS–WLAN–07/03
Features
• Integrates the IEEE 802.11b Physical Layer (Baseband) and the Media Access
Controller (MAC) for Supporting Standard Rates up to 11 Mbps
Supports Antenna Diversity Algorithm, Automatic Receive Gain Control, Transmit Gain
Control, Transmit Filter for Japanese Regulatory and Differential or Single-Ended I- and
Q-Baseband Signals
Integrates 160 KBytes of SRAM Organized in Five Banks of 32 KBytes Each, Offering
the Flexibility for individually Configuring Each of Them as Program or Data Memory
Zero Wait States for Program Execution
Fast Data Transfers through DMA Channels
Low Power ARM7TDMI
®
RISC Processor
Integrates a Bootstrap ROM Supporting Device Firmware Upgrade (DFU) Protocol and
USB Chapter 9 Compatibility
The Bootstrap Code Supports External SPI EEPROM for the Custom Configuration
Parameters Used during the Device Enumeration Phase as well as Default Parameters
for First Time EEPROM Programming
Glueless Parallel Flash Memory Interface, Supporting up to 128 KBytes of Nonvolatile
Memory
Glueless External SRAM Interface for All MAC Operations, Supporting up to
128 KBytes of External Memory
Wired Equivalency Privacy (WEP) in Hardware Supporting 64-bit and 128-bit Keys
Hardware Implementation of TKIP
Hardware Implementation of AES Encryption Supporting Various Modes
(CCM/CTR/CBC)
The WLAN Functions Can Be Easily Changed or Updated to New Requirements Since
They are Implemented in Microcode
Supports 11 Mbps Rates With Automatic Fallback to 5.5, 2 and 1 Mbps
SPI Interface and 9 GPIO Pins
144-ball LFBGA Package
Low-voltage 1.8V Core Operation
Block Diagram
Timers
External
Memory
Boot ROM
Interface
Internal
Memory
(SRAM)
Common Memor
y
Interf
ace Controller
ARM7TDMI
Decoder/
Arbiter/
Bridge
Interrupt
Controller
SPI Interface
802.11b
Baseband
MAC Support
Unit (MSU)
USB
Interface
Encryption/
Decryption
Block
1
Note: This is a summary document. A complete document is available
under NDA. For more information, please contact your local Atmel sales
office.