Definitions for

**"Square Wave"****Related Terms:**Sine wave, Oscillator, Vco, Amplitude, Sinusoidal, Harmonic distortion, Oscillograph, Resonant frequency, Harmonics, Local oscillator, Constructive interference, Full-wave rectifier, Function generator, Hum, Ripple, Rms value, Pulse , Phase locked loop, Intermodulation, Destructive interference, Total harmonic distortion, Discriminator, Emi/rfi, Pulse , Lfo, Electromagnetic interference, Oscillation, Phase lock loop, Phase noise, Resonance, Pulse width modulation, Interference, Fundamental frequency, Root mean square, Frequency, Harmonic, Heterodyne, Power spectrum, Phase-locked loop, Rms, Emi, Ripple and noise, Vswr, Half-wave rectifier, Resonant, Continuous wave, Ringing, Input, Microphone, Tesla coil

A wave shape that rises instantaneously to a constant value that is maintained for a set time interval, after which it instantaneously falls to a new value. The term "square" wave is a misnomer since, invariably, the wave shape produced is rectangular and not strictly square.

A waveform that jumps sharply but evenly from one extreme value to the next. |_|"|_|"|.

a kind of basic waveform

an acid test because the abrupt rise and fall (the jumps) severely test the transient and high-frequency response and the flat top (dead stop) severely tests for any tendency to ring

an approximation of a sine wave with abrupt up-and-down voltage transitions

an infinite sum of all the odd harmonics

a periodic waveform which consists of a fundamental and all the odd-numbered harmonics

a special-case rectangular waveform where the PW and SW are equal

a waveform that is built up from a series of harmonics derived from the fundamental frequency

It is an undesirable waveform for critical computing applications, as it is harder on equipment and may cause undesired side effects. (Compare to Sine Wave.)

A periodic wave that alternately assumes one of two fixed values (high and low) with the transition time between these two levels being negligible.

A waveform designed to simulate a transient impulse such as that of percussion instrument. Derived from a sine wave, a square wave can be shown by technical analysis to contain a multitude of harmonics. It is a very difficult test of hi-fi equipment and therefore particularly useful.

A rectangular wave output waveform having a 50% symmetry. If specified, the tolerance to the symmetry must be specified. TTL, LSTTL, CMOS and HCMOS outputs are described as square wave and comply to the wave form drawing at right.

A term for an electrical wave shape generated by a solid state power supply.

A common wave shape consisting of repeating square pulses.

An alternating or pulsating current or voltage whose wave shape is square.

A wave shape where the voltage rises instantly to one level, stays at that level, instantly falls to another level and stays at that level, and finally instantly rises to its original level to form each cycle.

Wave that alternates between two fixed values. Has very rapid (theoretically zero) rise and fall times. ___ ___ | | | | ___| |_______| |_____

A square or rectangular shaped periodic wave which alternately assumes two fixed value of near equal time duration in which the transition time is negligible in comparison with the duration item.

A waveform consisting of a fundamental and all the odd-numbered harmonics it produces. Because it consists of energy to at least the 20th harmonic, it can be used for frequency-response evaluation with electronic components. Any amplifier that can reproduce an exact 1-kHz fundamental square wave cleanly will be clean to 20 kHz.

A square wave is how a digital sound wave is distorted when driven to too high of levels. Very unpleasant sounding.

Describes an alternate AC waveform to sine wave or PWM sine wave. Considered by many to be the least desirable waveform for critical computing applications. Rather than the smooth arc typically associated with a sine waveform, a square waveform is entirely rectangular and may provide a challenge the operation of certain sensitive pieces of electronics when used continuously or for long duration. Before 1990, many standby UPS systems available provided square wave output in battery mode. Certain lower end power inverters still offer square wave output. See PWM sine wave and sine wave.

Output waveform generated by very basic, low-cost UPSs. Functions adequately for less sensitive loads, but may not provide acceptable quality input for some types of electronic equipment.

The simplest waveform that looks like a multiple step staircase or more like landing to landing at regular intervals. Some types of equipment behave strangely when run from a square wave.

Wave that alternates between two fixed values for an equal amount of time.

On a digital point, a specific pattern of on and off states, repeated continuously. Some Opto 22 brains, such as the serial B3000 and the Ethernet-based SNAP-PAC-EB1, can generate square waves through an output point on the I/O unit.

A special-case rectangular waveform that has equal pulse width and space width values.

A square wave is a basic kind of non-sinusoidal waveform encountered in electronics and signal processing. An ideal square wave alternates regularly and instantaneously between two levels, which may or may not include zero.