CSEM & RivieraWaves unveil world's lowest-power Bluetooth Smart integrated silicon IP solution

RivieraWaves and CSEM have teamed up to provide an ultra-low-power integrated Bluetooth Smart solution to meet the growing needs for wireless body-worn sensors for medicine, sports and wellness. This flexible solution for ASIC integration meets the challenging miniaturization and autonomy require-ments posed by such sensors with a small silicon area and power consumption so low that a regular button cell may provide several years of battery life.

The integrated solution, which combines RivieraWaves' fully qualified Bluetooth Smart protocol stack and baseband with the world's lowest-power Bluetooth Smart radio from CSEM, is now available for licensing. Samples are available, as well as a complete reference design, a smart phone demonstrator and evaluation kit.

The radio is based on CSEM's new icyTRX transceiver. With power consumption of less than 10mW in receive mode (from a 1.2V supply), it offers significant improvements over today's standard products, and features sensitivity of -94 dBm as well as settling time as low as 5us. A patented architecture and integration of all RF passive devices on-chip result in a silicon area of less than 2mm2 in a 90nm CMOS technology.

The Bluetooth Smart, or Bluetooth Low Energy, baseband controller has a gate count of less than 65K, including an optional AES-CCM128 engine. The hardware accelerator handles the real time tasks of the Bluetooth Smart Link Layer and takes care of a complete Bluetooth Smart event while the CPU is in sleep mode, an approach that is more energy efficient than a baseband controller with packet-driven architecture. Running at 8MHz, peak power consumption is around 100uA in a 90nm CMOS process. Power consumption in idle modes has also been reduced to the minimum. Innovative clock gating, power gating, and optimized software control means several years of battery life can be extracted from a regular CR2032 button cell.

The BLE software protocol stack has a low MIPS requirement and low memory footprint. It can easily be executed on a Cortus APS3 or ARM Cortex M0 running at 8MHz. The core stack for a health thermome-ter for instance can be as low as 50KB from link layer up to profile.