Heart rate variability monitoring and assessment system on chip

This paper describes a system on a chip for heart rate variability monitoring and assessment. The system design applies digital techniques to measure RR intervals from ECG signals, then categorizes and stores HRV measures in an internal memory. The system has been tested for functionality, synthesized and laid out in a 0.5 μm CMOS technology in a 3x3 mm²chip with less than 1.5 μW power dissipation. The chip detects all R peaks with millisecond accuracy after the initial 2 seconds of data, and stores up to 2 minutes of continuous ECG data and up to 4 minutes of HRV histogram. Compact size, low cost, and low power consumption make this chip suitable for employment in modern implantable and portable devices.