Standby power consumption goes into freefall

BlueCore6-ROM offers two optional scanning modes that dramatically reduce power consumption in handset applications.

Bluetooth devices typically spend the vast majority of time in Standby mode.  To extend the standby battery life of mobile phones, CSR has developed a new Conditional Scan mode.  This makes a Page Scan or Inquiry Scan conditional on the presence of RF energy in the Bluetooth band — which is determined by a rapid sweep of frequencies. If no energy is present, BlueCore6-ROM eliminates an unnecessary scan, saving up to 86% of power.  This feature relies on the fast and accurate RSSI (received signal strength indicator) circuitry embedded in BlueCore.

A second mode called Casual Scan saves power when a host system's VCTXO oscillator is shared by the Bluetooth device to save cost — a common practice in handset. Casual Scan mode synchronises BlueCore6-ROM's periodic wake-up to the same period as the host baseband.  This can save significant power (as the amount depends on the particular architecture, it is not possible to quote an accurate figure).

Two other factors also serve to reduce Bluetooth power consumption: BlueCore6-ROM's AuriStream and Tx/Rx capabilities.

If BlueCore6 is at both ends of the link, the AuriStream codec will provide better audio quality with a power reduction in handsets of around 40% (more…). In addition to this, BlueCore6-ROM (in QFN packaging) has an incredible radio link budget of +10 dBm Tx, -90 dBm Rx sensitivity. Depending on the implementation, this provides Class 1 performance without the cost and power consumption of an external power amplifier.