A 3-channel ECG measuring system for wireless applications

This paper describes the design and impementation of an integrated frontend for electrocardiographic (ECG) systems, realized in a 0.35 1/4m 2P4M CMOS process. The performance is optimized to adhere to the standard IEC60601-2-47, which defines the requirements for safety and essential performance of ambulatory ECG equipment. The system consists of three channels to measure the 3 leads of a Goldberger ECG monitoring scheme, therefore a single ended design structure was chosen to minimize the power consumption. A fourth channel is included for additional measurements. Each of the four channels contains a low power multi-bit sigma-delta modulator and a low power digital filter. Three channels are equipped with a low noise preamplifier. The supply voltage can be varied from 2.4 Volt up to 3.6 Volt. With a total power consumption of less than 2 mW the circuit is designed for battery operated equipment.