RANCANG BANGUN KALIBRATOR EKSTERNAL ELEKTROKARDIOGRAF 3 LEADS BERBASIS ATMega8535

As a medical instrument, electrocardiograph should have a high accuracy and precision in measuring the electrical potential of heart. Therefore, the calibration process is included as one of the procedures in using the electrocardiograph. Electrocardiograph can be calibrated internally and externally. At the University of Lampung the research to design and implement a simulator and calibrator has been done. However, the amplitude of output signal not conform the normal heart signal characteristics and electrocardiograph device specification. This study is a continuation to the previous research studies. In this study an external electrocardiograph calibrator was constructed which focuses on the attenuation of the signal amplitude by using a digital potentiometer, IC X9259. The value of IC’s attenuation is controlled by microcontroller ATMega8535 that sends the settings data of attenuation via I2C serial communication. The result of this research is a hardware that is capable of generating 3 type of electrocardiogram signals, lead I, lead II and lead III. However, the hardware is yet able to be functioned as an external calibrator for electrocardiograph because the amplitude of signals that generated range between 18.4 – 26.4 mVp-p. Which that range value does not conform with 0.5 – 4 mVp-p specifications of electrocardiograph device