博通BCM4325移动无线系统方案

博通（Broadcom）公司的BCM4325是低功耗单片IEEE 802.11a/b/g MAC/基带/收音机芯片，同时还集成了BLUETOOTH® 2.1 + EDR（增强数据速率）以及FM收音机，适用于低功耗移动手机和便携式应用．BCM4325采用先进的设计技术和工艺制造技术，提供最低的工作功耗和待机功耗，从而延长了系统电池寿命，维持了系统的连续连接，并提供了丰富的特性．本文介绍了BCM4325的主要特性，主要指标和方框图．

BCM4325 Low-Power 802.11a/b/g with Bluetooth® 2.1 + EDR and FM
SINGLE CHIP IEEE 802.11a/b/g MAC/BASEBAND/RADIO WITH INTEGRATED
BLUETOOTH® 2.1 + EDR AND FM RECEIVER FOR LOW-POWER MOBILE HANDSET AND HANDHELD APPLICATIONS
The Broadcom BCM4325 family of single-chip devices provides for the highest level of integration for a mobile or handheld wireless system, with integrated IEEE 802.11a/b/g (MAC/Baseband/Radio), Bluetooth 2.1 + enhanced data rate (EDR), and FM receiver. Thus providing a compact small form factor solution with minimal external components to drive the costs for mass volumes and allows for flexibility in size, form, and function of handheld devices. The BCM4325 is designed to address the needs of highly mobile devices that require minimal power consumption and reliable operation.
The BCM4325 utilizes advanced design techniques and process technology to deliver the lowest active and idle power, extending the system battery life while maintaining consistent connectivity, and still provides a rich set of features.

BCM4325主要特性：
WLAN Key Features
Single-band 2.4-GHz 802.11b/g or dual-band 2.4-GHz and 5-GHz 802.11a/b/g with Bluetooth 2.1 + EDR and FM receiver
Industry leading low-active transmit and receive power consumption and ultra-low power in stand-by and idle modes
Supports IEEE 802.11d/e (WMM, QoS, WMM-PS), h, i, j (upgrades available for k, r, w)
Supports IEEE 802.15.2 external three wire coexistence scheme to support additional wireless technologies such as GPS, WiMax, or UWB
Supports standard interfaces, SDIO v1.2 (1 bit and 4 bit), SPI, and high speed UART, for easy migration from the Broadcom 2 chip solution (BCM4328 + BCM2048)
Integrated CPU with on-chip memory for a complete WLAN subsystem minimizing the need to wake up the applications processor
Fractional nPLL allows support for a wide range of reference clock frequencies

Security:
-WPA- and WPA2 (personal) for powerful encryption and authentication
-AES and TKIP in hardware for faster data encryption and 802.11i compatibility
-Supports Cisco® Compatible Extensions (CCX - CCX4.0)
-SecureEasySetup™ for simple Wi-Fi setup and WPA2/WPA security configuration
Worldwide regulatory support—Global products supported with worldwide homologated design
Bluetooth Key Features
Bluetooth Specification version 2.1 + EDR (up to 3 Mbps) compliant, with provisions for supporting future specifications
Supports extended synchronous connections (eSCO) for enhanced voice quality by allowing for retransmission of dropped packets
Adaptive frequency hopping (AFH), for reducing radio frequency interference.

Interfaces support—Host controller interface (HCI) using a high-speed UART interface and PCM for audio data
The FM unit supports BSC (Broadcom Serial Control) for communications, stereo analog output, as well as I²S and PCM interfaces.

Integrates the InConcert collaborative WLAN coexistence, including the 802.15.2 three-wire coexistence support
Low-power consumption improves battery life of handheld devices
76-MHz to 108-MHz FM bands and supports European Radio Data Systems (RDS) and North American Radio Broadcast Data Systems (RBDS) modulations
Supports dual-A2DP for stereo sound
Automatic frequency detection for standard crystal and TCXO values
General Features
One driver software architecture for easy migration from existing embedded WLAN and Bluetooth devices as well as future devices
Support battery voltage range from 2.3V to 5.5V supplies with the internal switching regulator
BCM4325主要指标：





图１．BCM4325方框图