Electrocardiogram (ECG) is the process of recording the electrical activity of the heart with help of the electrodes placed on the skin surface. ECG recordings are one of the most useful tools used to diagnose heart diseases. In this study reference circuit design which produces ECG signal was performed. Signals which are simulated were sampled and the calculated values were converted into pulse width modulation outputs and transferred to Arduino. Analog signal outputs of the simulated signals were observed on the oscilloscope. Because the waveforms of the signals are generated correctly by the simulator, it can be used during the calibration of ECG devices or for educational purpose.