Cambridge, UK-based CSR has launched a fourth generation of its Bluetooth silicon, designed for Enhanced Data Rate (EDR) Bluetooth which is being officially launched today by the Bluetooth Special Interest Group (SIG) at WiCon World, in Amsterdam, in the Netherlands.
CSR’s BlueCore4 will deliver data rates which are three-times faster than current v1.2 Bluetooth devices, as well as lower power consumption for Bluetooth mobile phones or headsets. BlueCore4 is sampling now with major OEM customers. Bluetooth EDR offers maximum data transfer rates of 2.1 Bbit/sec compared to the current 721 kbit/sec for v1.2 standard rate.
This increase in transfer rate also means that, for a given amount of data, the EDR radio will be active up to 3 times less than a v1.2 radio, hence reducing power consumption, which greatly benefits battery-dependent mobile devices.
CSR BlueCore4 is fully backwards compatible with existing Bluetooth v1.1 and v1.2 devices. Bluetooth EDR achieves its higher data rates by using a Phase Shift Keying (PSK) modulation scheme in place of the Gaussian Frequency Shift Keying (GFSK) of standard rate. This allows more bits to be transmitted in each symbol of the packet-payload when it is sent over the radio link. However, the symbol rate is still 1 Megasymbol per second, the packet timing and structure are the same, the spectral characteristics of transmissions are virtually unchanged and support for both modulation schemes is mandatory for all EDR capable products.
CSR BlueCore4 is being made available in two variants – one for use with external Flash memory, and one with mask-ROM. BlueCore4-External, supplied in an 8x8mm BGA (ball grid array) package, is a solution for markets that demand the ability to upgrade quickly.
With the Bluetooth firmware committed to on-chip ROM, CSR BlueCore4-ROM is less expensive and sports a much smaller footprint (3.8x4mm in a chip-scale package, or 6x6mm in a BGA which is pin-compatible with BlueCore2-ROM and BlueCore3-ROM). The ROM chip’s size and cost suit it to mobile phones, headsets and other mass-production, cost-sensitive applications which require Bluetooth functionality to be integrated.
BlueCore4 offers increased on-board RAM of 48 KB compared to 32 KB on previous BlueCore silicon. Some of this extra memory is required for additional buffer space to handle the Enhanced Data Rate, while the rest ensures that future specifications such as ‘Scattermode’ will be fully supported.
CSR is sampling BlueCore4-External now, with full production in September. BlueCore4-ROM will sample in Q3 2004 with mass production planned to start in Q4 2004.