Digital Electronics Unit 1.2
Breadboard
A circuit board for wiring temporary circuits, usually used for prototypes or laboratory work
Insulator
A material that does not allow current to flow when voltage is applied because of its high resistance
Current
A movement of electrical charges around a closed path or circuit
Digital Multi-Meter
A piece of test equipment used to measure voltage, current, and resistance in an electronic circuit
Oscilloscope
A piece of test equipment used to view and measure a variety of different waveforms
Digital Waveform
A series of logic 1s and 0s plotted as a function of time
Digital
A way of representing a physical quantity by a series of binary numbers. Can only be specific discrete values
Analog
A way of representing some physical quantity, such as temperature or velocity, by a proportional continuous voltage or current. Can have any value in a defined range.
Square Wave
An almost instantaneous rise and decay of voltage or current in a periodic pattern with time and with a constant peak value
Conductor
Any material that allows the free movement of electric charges, such as electrons, to provide an electric current
Electron
Basic particle of negative charge in orbit around the nucleus in an atom
Electron Flow
Current of negative charge in motion. Direction is from the negative terminal of the voltage source to the positive side. Opposite to the conventional current
Clock
Digital signal in the form of a rectangular pulse train or a square wave
Duty Cycle
Fraction of the total period that a digital waveform is in the high state. DC = th/T
Sine Wave
One in which amplitude varies in proportion to the sine function of an angle
Series Circuit
One that has only one path for current
Parallel Circuit
One that has two or more branches for separate current from one voltage source
Resistance
Opposition to current. Unit is the ohm
Proton
Particle with a positive charge in the nucleus of an atom
555 timer
TTL- compatible IC that can be wired to operate in several different modes, such as a one-shot and an astable multivibrator
Simulation
Testing design function by specifying a set of inputs and observing the resultant outputs. Generally shown as a series of input and output waveforms
Kirchhoff's Current Law
The algebraic sum of all currents in a series curcuit equal the total current supplied by the source
Kirchhoff's Voltage Law
The algebraic sum of all voltages in a parallel circuit equal the total voltage supplied by the source
Period
The amount of time required for one complete cycle of a periodic event or waveform
Conventional Current
The direction of current flow associated with positive charge in motion. The current flow direction is from a positive to negative potential, which is in the opposite direction of electron flow
Logic High
The higher of two voltages in a digital system with two logic levels
Amplitude
The instantaneous voltage of a waveform
Logic Low
The lower of two voltages in a digital system with two logic levels
Nucleus
The massive, stable part of the atom that contains both protons and neutrons
Frequency
The number of cycles per unit time of a periodic waveform
Falling Edge
The part of a pulse where the logic level is in transition from a high to a low
Atom
The smallest particle of an element
Hertz
Unit of frequency. Equals one cycle per second
Ohms
Unit of resistance
Ohm's Law
V=IR