1 / 32

Lecture 2: Circuit Elements and Series/Parallel Resistors Nilsson 2.1-2.5, 3.1-3.2

Lecture 2: Circuit Elements and Series/Parallel Resistors Nilsson 2.1-2.5, 3.1-3.2. ENG17 (Sec. 1): Circuits I Summer 1 2014. June 24, 2014. Overview. Voltage & Current Sources Electrical Resistance Circuit Model Kirchhoff’s Laws Dependent Sources Series / Parallel Resistors.

Download Presentation

Lecture 2: Circuit Elements and Series/Parallel Resistors Nilsson 2.1-2.5, 3.1-3.2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Lecture 2:Circuit Elements and Series/Parallel ResistorsNilsson 2.1-2.5, 3.1-3.2 ENG17 (Sec. 1): Circuits I Summer 1 2014 June 24, 2014

  2. Overview • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources • Series / Parallel Resistors

  3. 5 Ideal Basic Circuit Elements • Voltage Sources • Current Sources • Resistors • Inductors • Capacitors

  4. Ideal Sources Voltage Source (const. voltage) Current Source (const. current)

  5. Dependent Sources Voltage Sources Current Sources

  6. Schematics

  7. Schematics (w/dependents)

  8. Schematics - GND • Ground (GND) is a common connection • Typically connect to Earth GND • Always a zero [V] reference potential

  9. Overview • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources • Series / Parallel Resistors

  10. Ohm’s Law

  11. Conductance • Conductance, G • Units: siemens [S]

  12. Power & Ohm’s Law Ohm’s Law Power Relationship Therefore…

  13. Examples

  14. Overview • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources

  15. Designing a Circuit Model

  16. Additional Elements Short Circuit Open Circuit Switch

  17. Schematic 1.5V 9V

  18. Overview • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources • Series / Parallel Resistors

  19. The Setup

  20. Kirchhoff’s Current Law (KCL) The algebraic sum of all the currents at any node in a circuit equals zero. • Therefore: • Assign signs to currents at each node • Positive (+) for current leaving a node • Negative (-) for current entering a node • Or vice versa

  21. Kirchhoff’s Voltage Law (KVL) The algebraic sum of all the voltages around any closed path in a circuit equals zero. • Therefore: • Assign signs to voltages in a loop • Positive (+) for voltage rise • Negative (-) for voltage drop • Or vice versa

  22. Observations • 7 equations  4 equations • Because I and V are related through R, we only need one • With only 2 branches at a node (in series), we only need to know 1 current

  23. KCL Example

  24. KVL Example

  25. Overview • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources • Series / Parallel Resistors

  26. Finding vo

  27. Finding vo KVL: KCL: Ohm’s Law:

  28. Overview • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources • Series / Parallel Resistors

  29. Series Connected Elements • Resistors in series carry the same current • KCL proves this • Resistors in series can be summed • KVL proves this

  30. Parallel Connected Elements • Resistors in parallel have same voltage across their terminals • KVL proves this • Resistors in parallel can be summed inversely • KCL proves this • Conductances are summed

  31. Example

  32. Recap • Voltage & Current Sources • Electrical Resistance • Circuit Model • Kirchhoff’s Laws • Dependent Sources • Series / Parallel Resistors

More Related