博通(Broadcom)公司的BCM2048是單片藍牙2.1+EDR兼容的基帶處理器/2.4GHz收發器,并集成了FM和RDS/RBDS接收器,具有做高的集成度,不需要外接關鍵元件,因材施教為實現藍牙和FM解決方案有最低限度的占位面積和藹系統成本.BCM2048廣泛應用在手機和智能手機,PDA和MP3.本文介紹了BCM2048的藍牙特性, FM+RDS收音機特性以及主要優勢,功能方框圖以及手機應用方框圖.
The Broadcom BCM2048 is a monolithic single-chip, Bluetooth® 2.1 + EDR-compliant, baseband processor/2.4-GHz transceiver with an integrated FM and RDS/RBDS receiver. It features the highest level of integration and eliminates all critical external components, thus minimizing the footprint and system cost of implementing a Bluetooth and FM solution.
The BCM2048 is the optimal solution for any voice and/or data application that requires the Bluetooth SIG standard Host Controller Interface (HCI) via a high-speed UART and PCM. The BCM2048 incorporates all Bluetooth 2.1 + EDR features including Secure Simple Pairing, Extended Inquiry Response, eSCO, AFH, fast connect, and all EDR packet types and lengths. The BCM2048 also includes InConcert and other industry-standard collaborative coexistence solutions with WLAN systems.
The BCM2048 Bluetooth radio transceiver provides enhanced radio performance to meet the most stringent industrial temperature applications and the tightest integration into mobile handsets and portable devices. It is fully compatible with any of the standard TCXO frequencies and provides full radio compatibility to operate simultaneously with GPS and cellular radios. The BCM2048 also features an on-chip Class 1 power amplifier for higher transmit output power, providing a cost-effective solution for improved communications with other Bluetooth devices such as wireless headsets.
The BCM2048 also integrates a complete FM and RDS/RBDS solution. The integrated solution saves power, external BOM, board space, and maximizes interface flexibility over a separate Bluetooth and FM solution. The FM subsystem can operate independently of Bluetooth and achieve full performance while Bluetooth is operating. It is designed to
cover from 76-MHz up to 108-MHz bands (US, Europe, Japan) and to operate from either the Bluetooth reference clock or a 32-kHz LPO input. The FM subsystem supports conventional I2C-compatible interfaces and analog outputs for legacy systems, as well as digital interface options, such as I2S and PCM. The I2S and PCM interfaces support
48-kHz operation and can be either master or slave. The analog interface consists of high-quality line-level stereo DACs.
The BCM2048 FM subsystem includes advanced RDS/RBDS capability. The BCM2048 synchronizes, demodulates, and decodes RDS/RBDS signals including CRC processing, post data filter detection, signal quality estimation, and buffering, thus making it easy for an external application to read and process the RDS/RBDS data.
The FM radio reception performance is very high with 1-uV for 26-dB (S+N)/N typical sensitivity and typically 60-dB SNR quality, making it easier on system integration and antenna design. The FM subsystem includes many sought-after features including signal dependant mono/ stereo blend, soft mute, and signal bandwidth control. The FM subsystem has digital RSSI signal quality and IF frequency error indicators for system monitoring. Embedded in the FM subsystem are auto search and scan features and large RDS data buffers to simplify interfacing with an external host.
The block diagram above illustrates how the BCM2048 can be used in a cellular application.

BCM2048藍牙特性:
Monolithic single die integration of Bluetooth® and FM Radio
Bluetooth specification 2.1 + EDR compliant with all data packet types and lengths supported
Best-in-class Bluetooth radio based on the proven BCM2045 core
On-chip integrated Class 1 power amplifier (PA) with programmable power control
Integrated InConcert® 2-wire as well as industry standard 3-wire collaborative coexistence with WLAN systems
No factory alignment required
5.5 Volt preregulator allows direct connect to lithium batteries
Improved Bluetooth transport with 4-Mbaud UART
Includes numerous enhancements for lower power dissipation
ROM-based solution with flexible code patching
Available in WLBGA 0.4 mm ball pitch and FPGA 0.5 mm ball pitch packages

BCM2048FM+RDS收音機特性:
76-MHz to 108-MHz FM bands supported (US, Europe, and Japan)
Excellent radio performance with 1 uV sensitivity for 26 dB (S+N)/N
FM control through either I2C-compatible interface or Bluetooth HCI
Signal dependant stereo/mono blending
Signal dependant soft mute
Auto search and tuning modes
Audio silence detection
RSSI, IF frequency, status indicators
RDS and RBDS demodulator and decoder with filter and buffering functions
Operates from 32 kHz or reference clock inputs
Flexible output interfaces including PCM, I2S, and analog stereo DAC and drivers.
Integrated FM and RDS receiver with only one external cap, one external inductor and optional antenna matching
BCM2048優勢:
On-chip Class 1 PA maintains a robust link over an extended range
Low external BOM cost and small area with 10 external RLC components. The PCB footprint is < 35 mm2 area.
Operates directly from a lithium battery or from fixed voltages down to 1.65 Volt
Best-in-class RF performance for longest range and ease of system integration
Full featured FM system with RDS/RBDS capability
FM system can operate independently from Bluetooth
Highly flexible interfaces for control and data/audio routing
Improved power dissipation for longer battery life
BCM2048應用:
Mobile handsets and smart phones
Personal digital assistants
Mobile MP3 players


圖1.BCM2048功能方框圖

圖2.BCM2048手機應用方框圖