1. Reflection suppression methods EECS 713 Liyao Wang

2. Outlines  Theory  Simulation circuit  Termination Source termination Load termination Thevenin termination RC termination Diode termination

3. Theory Figure_1

4. Theory Figure_2 [1] Figure_3 [1]

5. Simulation circuit

6. Simulation Result

7. Source termination Advantage 1)Easy to assemble 2)Reduce ringing 3)Increase signal integrity 4)Reduce EMI Disadvantage 1)Load reflection still there 2)Increase the rise time of input signal 3)Wasting power

8. Source termination

9. Simulation result

10. Load termination Advantage 1)Easy to assemble 2)Reduce ringing 3)Easy to find the resistor value Disadvantage 1)Increase power consumption

11. Load termination

12. Simulation result

13. Thevenin termination

14. Advantage 1)Good overshoot suppression Disadvantage 1)Large current drive (increase power consumption) 2)Increase the difficulty of layout 3)Hard to choose the resistor value and Vcc value

15. Thevenin termination

16. Simulation result

17. RC termination Advantage 1)Absorbing all the reflection wave 2)Low power consumption Disadvantage 1)Increase signal delay 2)The time constant of RC circuit may cause reflection 3)In high speed digital design, need to be careful of the capacitor value

18. RC termination

19. Simulation Result

20. Reference [1] Paul, Clayton R., Introduction to Electromagnetic compatibility, Wiley Series in Microwave and Optical Engineering, 2006. [2]Wakerly, John F., Digita l Design Principles and Practices, Pearson Education, Inc., 2006. [3] R. Jagdale, A. Reddy, and K. Sundeep, “Optimization of reflection issues in high speed printed circuit boards,” in Proceedings of the 12th International Conference on Networking, VLSI and Signal Processing, pp. 108–112, World Scientific and Engineering Academy and Society, 2010