Introduction to Analog

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(DMM)

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. A digital representation can have only specific discrete values.

Analog

A way of representing some physical quantity, such as temperature or velocity, by a proportional continuous voltage or current. An analog voltage or current can have any value within 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 changes, 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 charges in motion. Direction is from the negative terminal of the voltage source, through the external, circuit, and returning to the positive side of the source. Opposite to the direction of conventional current.

Clock

Digital signal in the form of a rectangular pulse train or a square wave.

Duty Cycle (DC)

Fraction of the total period that a digital waveform is in the HIGH state. DC = th/T (often expressed as a percentage: %DC = th/Tx100%).

Ohm's Law

In electric circuits, I=V/R.

Sine Wave

One in which amplitude varies in proportion to the sine function of an angle.

Series Circuit

One that has only one path 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 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. Simulation is generally shown as a series of input and output waveforms.

Kirchhoff's Current Law (KCL)

The algebraic sum of all currents into and out of any branch point in a circuit must equal zero.

Kirchhoff's Voltage Law (KVL)

The algebraic sum of all voltages around any closed path must equal zero.

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. Often used to mean maximum amplitude, or peak voltage, or a pulse.

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 that still has the same characteristics as the element.

Hertz (Hz)

Unit of frequency. One hertz equals one cycle per second.

Ohms

Unit of resistance. Value of one ohm allow current of one ampere with potential difference of one volt.