Bluetooth continues to expand quietly into major wireless applications. The highest-volume applications are cell phones and wireless headsets. With many millions sold and Bluetooth prices at an all-time low, PC manufacturers like Apple and Dell are also incorporating it into keyboards and mice, as well as providing PDA synchronization. Beyond that, new applications include telematics in automobiles and wireless barcode readers.
The latest single-chip Bluetooth radios from Cambridge Silicon Radio provide the first complete implementation of the revised Bluetooth standard v1.2. Their primary feature is adaptive frequency hopping (AFH) technology, which facilitates coexistence between competing 2.4-GHz Bluetooth and 802.11b/g wireless local-area network (WLAN) radios. With AFH, the Bluetooth transceiver skips over frequency channels used by adjacent 802.11b/g radios. Both 802.11b/g-enabled devices can then incorporate Bluetooth with minimum interference.
The BlueCore3-ROM version incorporates built-in flash memory, eliminating the need for external flash. Such increased integration not only reduces size and lowers costs, it also consumes 18% less current than previous implementations. The ROM incorporates the Bluetooth stack up to the host connection interface (HCI). The upper layers of the software stack then run on the host processor.
An intriguing new version of BlueCore3, the Multimedia version, was designed for wireless audio applications. This single-chip radio includes CSR's own programmable DSP, where special features such as filtering, noise or echo cancellation, or even special audio protocols (MP3) may be implemented.
Also on-chip are two 16-bit audio codecs with dual analog-to-digital and digital-to-analog converters for full stereo audio. Microphone and speaker amplifiers are fully integrated as well. This chip is designed for wireless headphones, but other applications like wireless speakers will surely emerge.
Samples of these chips will be available in late July with full production available at the end of September. Contact CSR for pricing.
Cambridge Silicon Radiowww.csr.com