SWITCHINGPowerPoint PresentationDigital Switch - TransistorTransistor controlling the circuitMeasuring Output before the transistorNAND – Not ANDSWITCHING•The modern computer is a digital and electronic device.•Runs on flow of electrons - movement of electrons from outer valence shells on atoms•Requires force/energy to pull an electron out of a shell - Electro-motive force (EMF) - Voltage•How tightly the electrons are held determines how much voltage is needed and is quantified as resistance•Number of Electrons flowing is quantified as Amperes•Computers are electronic switching devices•Voltage source (battery)•Meter to detect voltage differential050505Short Circuitlarge voltage flow, but no voltage differentialDigital Switch - Transistor•Computers are constructed from transistors•Transistor are used as on-off switches (0-off, 1-on), hence binary0505Transistor controlling the circuit0505Measuring Output before the transistor•Acts as an invertor•No voltage on the input causes the meter to read 5 volts•A voltage on the input causes the meter to read zero0505NAND – Not ANDA B Out0 0 10 1 11 0 11 1