1. Design of Electrocardiogram (ECG) System
NASSER AL-SOLIMAN
HASSAN AL-TAMIMI
AMER AL-KTHERE
Biomedical Technology Department
College of Applied Medical Sciences
Salman Bin Abdul-Aziz University

2. Abstract
This research deals with the design of electrocardiogram (ECG) system that measures heart signals. The design is based on discrete electronics components that reduce the cost of the system. The system consists of 3-op-amp instrumentation amplifier, band-pass filter with bandwidth of 0.05Hz - 100Hz, mains frequency notch filter and a total gain of A stand alone split power supply is designed to power the system. The ECG system is tested using medical ECG electrodes and typical ECG signals were recorded from some volunteers.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

3. - Design of a typical 3-leads ECG system.
Research Objectives
- Practicing the design of low cost medical devices.
- Design of a typical 3-leads ECG system.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

4. Design and testing of ECG system using discrete components.
Research Problem
Design and testing of ECG system using discrete components.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

5. Introduction to ECG
The electrical activity associated with heart muscles travels through various tissues and reaches the surface of the body where it can be detected by electrodes applied to the skin. The record obtained from the depolarization and repolarization voltages of the heart muscle is called an electrocardiogram or ECG [1], [2].
Biomedical Technology Department
College of Applied Medical Sciences
Salman Bin Abdul-Aziz University

6. ECG System Specifications
- Three Op-amp Instrumentation amplifier (IA) and an inverting amplifier with total gain of 1000.
- Band Width 0.05 – 100 Hz (Low Pass Filter (LPF) and High pass Filter (HPF)).
- Notch Filter centered at 60Hz.
- CMRR =80 dB
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

7. The project block diagram
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

8. ECG designed Power supply
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

9. Split Power Supply Design
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

10. Instrumentation Amplifier Circuit Diagram
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

11. Band Pass Filter circuit diagram
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

12. A Notch Filter centered at 60 Hz.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

13. Constructed ECG circuit
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

14. ECG System setup and testing
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

15. Research Outputs
1. An operating ECG system is designed and tested. 2. ECG signals were recorded and displayed.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

16. Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

17. ECG Signal Results Before the Notch Filter.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

18. ECG Signal Result After the Notch Filter
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

19. CONCLUSIONS
The constructed single-channel ECG amplifier is capable of acquiring a satisfactory reading of rest ECG signal. It can be expanded to be a multi-channel ECG system capable of recording the standard 12-Lead system.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University

20. References
[1] Bronzino, J.D., The Biomedical Engineering Handbook. CRC Press, Inc., 1995.
[2] Carr, J.J. and J.M. Brown, Introduction to Biomedical Equipment Technology. Prentice Hall, Inc., 3rd ed., 1998.
Biomedical Technology Department College of Applied Medical Sciences Salman Bin Abdul-Aziz University