Microwatt embedded processor platform for medical system-on-chip applications

A medical system-on-chip (SoC) that integrates an ARM Cortex-M3 processor is presented. Ultra-low power operation is achieved via 0.5-1.0 V operation, a 28 fW/bit fully differential subthreshold 6T SRAM, a 90%-efficient DC-DC converter, and a 100-nJ fast Fourier transform (FFT) accelerator to reduce processor workload. Using a combination of novel circuit design, system architecture, and SoC implementation, the first sub-microwatt per channel electroencephalograph (EEG) seizure detection is demonstrated.