1. 1 Dr. Cynthia Furse University of Utah Dr. Cynthia Furse University of Utah Introduction to Electrical & Computer Engineering Inductors

2. Inductors What is Inductance ? How does it relate to magnetic field & Current? Explain the effect of µ, N, S, l What does it do to a voltage and current? 2

3. Inductors Passive element that stores energy in magnetic field Solenoid Wound Inductor All rights reserved. Do not copy or distribute. © 2013 National Technology and Science Press Circuits, Second Edition by Fawwaz T. Ulaby and Michel M. Maharbiz, © NTS Press, Used with Permission by the Publisher Magnetic permeability µ=µo µr µo = 1.26 x 10(-6) H Henries

4. Current and Magnetic field 4

5. Wire Wound Inductor 5 http://www.murata.com/products/emicon_fun/2011/03/inductor_en14.html

6. Multilayer Inductor 6 http://www.murata.com/products/emicon_fun/2011/03/inductor_en14.html

7. Thin Film Inductor 7 http://www.murata.com/products/emicon_fun/2011/03/inductor_en14.html

8. Electrical Properties of Inductors Inductance – current, charge, voltage, power, energy What happens at DC? Series and Parallel 8

9. Inductors Passive element that stores energy in magnetic field At dc, inductor looks like a short circuit Current through inductor must be continuous (no abrupt change) Solenoid Wound Inductor All rights reserved. Do not copy or distribute. © 2013 National Technology and Science Press Circuits, Second Edition by Fawwaz T. Ulaby and Michel M. Maharbiz, © NTS Press, Used with Permission by the Publisher

10. 10 http://hyperphysics.phy-astr.gsu.edu/hbase/electric/indtra.html

11. Inductors: Current & B Field Circuits, Second Edition by Fawwaz T. Ulaby and Michel M. Maharbiz, © NTS Press, Used with Permission by the Publisher Current = begins to flow and starts to create magnetic field

12. Inductors: Current & B Field Circuits, Second Edition by Fawwaz T. Ulaby and Michel M. Maharbiz, © NTS Press, Used with Permission by the Publisher Current = begins to flow in and starts to create magnetic field At t=0, this acts like an OPEN circuit Voltage is high, current is low

13. Inductors: Current & B Field Circuits, Second Edition by Fawwaz T. Ulaby and Michel M. Maharbiz, © NTS Press, Used with Permission by the Publisher When magnetic field is established, current flows freely At t=∞, this acts like a SHORTcircuit Voltage is low, current is high

14. What does an inductor do to the current ? 14

15. What does an inductor do to the current ? 15 Vs/R 66% at t=L/R 

16. What does an inductor do to the voltage ? 16 Vs 36% at t=L/R 

17. What does an inductor do to a voltage and current? t=0: OPEN CIRCUIT t=∞: SHORT CIRCUIT 17 Voltage changes Instantly Current changes slowly At ‘steady state’ Voltage =0 At ‘steady state’ Current is Vs/R

18. 18 http://macao.communications.museum/eng /exhibition/secondfloor/moreinfo/2_3_6_Re sistanceInductance.html

19. Inductors in Series & Parallel 19

20. How can we use Inductors? Resonators (synthesizers) Matching Impedances AC Choke Transformers Inductive coupling 20 http://www.murata.com/products/emicon_fun/2011/03/inductor_en14.html

21. Inductive Coupling 21 http://www.ferroxtag.com/RFID/CP.LFHFUHF.htm

22. Inductive Coupling: Electric Wave Buses (UofU) 22

23. Blackrock Microsystems 23 http://www.blackrockmicro.com/content.asp x?id=60

24. Passive RFID 24

25. Transformers 25

26. Transformers 26

27. Low Pass filter Noise Filter / Integrator 27

28. High Pass Filter DC Block / Differentiator 28

29. 29 Dr. Cynthia Furse University of Utah Dr. Cynthia Furse University of Utah White Canyon, American Fork