Abstract
A recorder consists essentially of an ECG (Electrocardiogram) amplifier, a LCD (Liquid Crystal Display), a SD (Secure Digital) memory card and a PIC (Peripheral Interface Controller). ECG waveforms induced from a human body are amplified and digitized by built-in AD (Analog-to-digital) converter in a PIC. Waveform data is simultaneously recorded on a SD Card and displayed on a LCD. These functions are controlled by a PIC. Basic electrical characteristics of a recorder were measured in this experiment. The continuous 12-bit AD conversion of sampling frequency of up to 500 Hz was available. A recorder operating at system clock frequency of 10 MHz consumed an electric current of 19 mA and can be continuously recording for about 100 hours using alkaline AAA batteries.
