Advanced Design Applications Power and Energy © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications Teacher Resource Learning Cycle 2

Polarity Sensitive and Storage Components © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Various Components Inductors Capacitors Diodes LEDs Transistors © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Inductors L Symbol: L Measured in Henrys (H) When a switch is closed, current in the inductor is stored © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Inductors continued Inductors in Series… L eq = L 1 + L 2 + … + L n Inductors in Parallel… 1/L eq = 1/L 1 + 1/L 2 + … + 1/L n © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Inductor - schematic symbol Iron core or choke Air core Powdered iron core © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Capacitors C Symbol: C Measured in Farads (F) micro (μ) or pico (p) When a switch is closed, two charged bodies are not in contact but positioned closely. No electron flow is present, but an electric force will exist. © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Capacitors continued Capacitors in Parallel… C eq = C 1 + C 2 + C 3 + … Capacitors in Series… 1/C eq = 1/C 1 + 1/C 2 + 1/C 3 + … © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Capacitor - schematic symbol Disc capacitor Electrolytic capacitor © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Diodes These components are also called rectifiers Function: to convert AC current into DC current Alternating current (AC) travels in both directions Direct current (DC) travels in one direction © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Diode schematic symbol One-way valve that will permit electron flow against the arrow in the symbol. Cathode marked with a bar Anode marked with a triangle © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

LEDs Light Emitting Diodes These are solid-state devices that emit light when voltage is applied across the semiconductor. The device is polarized. Polarity of voltage applied to the leads is critical. © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

LEDs Voltage Requirements Light-Emitting Diodes Never connect an LED to a 9V battery. You must use a resistor of at least 100Ω in series. It will also not work with voltage as low as 1.5V (AA batteries). Requires at least +2.3VDC to operate. © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

LED schematic symbol Simplified Standard © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Transistor An important development in the 20th century. Enabled the invention of the IC (integrated circuit), which is present in high-tech electronic devices (computers, cell phones, calculators). Inventors: John Bardeen, Walter Brattain, William Shockley. Use lower amounts of electricity, smaller in size, and produce less heat than vacuum tubes. © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Transistor continued The transistor is a three-lead device: Base – connects leads Collector – collects charges Emitter – supplies charges © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications Able to: Amplify weak signals Switch higher current loads with small signal input Perform various circuit functions

Transistor Types Two types NPN PNP First section is emitter Second is base Last is collector © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications

Transistor schematic symbol © 2014 International Technology and Engineering Educators Association STEM  Center for Teaching and Learning™ Advanced Design Applications