Runt pulse

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In digital circuits, a runt pulse is a narrow pulse that, due to non-zero rise and fall times of the signal, does not reach a valid high or low level. A runt pulse may occur when switching between asynchronous clocks; or as the result of a race condition in which a signal takes two separate paths through a circuit, which may have different delays, and is then recombined to form a glitch; or when the output of a flip-flop becomes metastable.

Pulse (signal processing) concept in signal processing

A pulse in signal processing is a rapid, transient change in the amplitude of a signal from a baseline value to a higher or lower value, followed by a rapid return to the baseline value.

In electronics, when describing a voltage or current step function, rise time is the time taken by a signal to change from a specified low value to a specified high value. These values may be expressed as ratios or, equivalently, as percentages with respect to a given reference value. In analog electronics or digital electronics, these percentages are commonly the 10% and 90% of the output step height: however, other values are commonly used. For applications in control theory, according to Levine, rise time is defined as "the time required for the response to rise from x% to y% of its final value", with 0% to 100% rise time common for underdamped second order systems, 5% to 95% for critically damped and 10% to 90% for overdamped ones. According to Orwiler, the term "rise time" applies to either positive or negative step response, even if a displayed negative excursion is popularly termed fall time.

In electronics, fall time is the time taken for the amplitude of a pulse to decrease (fall) from a specified value to another specified value.


Some oscilloscopes provide a method for triggering on runt pulses. The oscilloscope triggers when the signal crosses one of two voltage thresholds, but not both. [1]

Oscilloscope type of electronic test instrument

An oscilloscope, previously called an oscillograph, and informally known as a scope or o-scope, CRO, or DSO, is a type of electronic test instrument that graphically displays varying signal voltages, usually as a two-dimensional plot of one or more signals as a function of time. Other signals can be converted to voltages and displayed.

Threshold voltage

The threshold voltage, commonly abbreviated as Vth, of a field-effect transistor (FET) is the minimum gate-to-source voltage VGS (th) that is needed to create a conducting path between the source and drain terminals. It is an important scaling factor to maintain power efficiency.

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Logic analyzer

A logic analyzer is an electronic instrument that captures and displays multiple signals from a digital system or digital circuit. A logic analyzer may convert the captured data into timing diagrams, protocol decodes, state machine traces, assembly language, or may correlate assembly with source-level software. Logic analyzers have advanced triggering capabilities, and are useful when a user needs to see the timing relationships between many signals in a digital system.


A monostable multivibrator is an electronic circuit that generates an output pulse. When triggered, a pulse of pre-defined duration is produced. The circuit then returns to its stable state and produces no more output until triggered again.

In digital circuit theory, sequential logic is a type of logic circuit whose output depends not only on the present value of its input signals but on the sequence of past inputs, the input history as well. This is in contrast to combinational logic, whose output is a function of only the present input. That is, sequential logic has state (memory) while combinational logic does not.

Waveform monitor

A waveform monitor is a special type of oscilloscope used in television production applications. It is typically used to measure and display the level, or voltage, of a video signal with respect to time.

In electronic instrumentation and signal processing, a time to digital converter is a device for recognizing events and providing a digital representation of the time they occurred. For example, a TDC might output the time of arrival for each incoming pulse. Some applications wish to measure the time interval between two events rather than some notion of an absolute time.

Pulse generator

A pulse generator is either an electronic circuit or a piece of electronic test equipment used to generate rectangular pulses. Pulse generators are used primarily for working with digital circuits, related function generators are used primarily for analog circuits.

Gee-H, sometimes written G-H or GEE-H, was a radio navigation system developed by Britain during World War II to aid RAF Bomber Command. The name refers to the system's use of the earlier Gee equipment, as well as its use of the "H principle" or "twin-range principle" of location determination. Its official name was AMES Type 100.

Arbitrary waveform generator piece of electronic test equipment used to generate electrical waveforms

An arbitrary waveform generator (AWG) is a piece of electronic test equipment used to generate electrical waveforms. These waveforms can be either repetitive or single-shot in which case some kind of triggering source is required. The resulting waveforms can be injected into a device under test and analyzed as they progress through it, confirming the proper operation of the device or pinpointing a fault in it.

Capacitor discharge ignition

Capacitor discharge ignition (CDI) or thyristor ignition is a type of automotive electronic ignition system which is widely used in outboard motors, motorcycles, lawn mowers, chainsaws, small engines, turbine-powered aircraft, and some cars. It was originally developed to overcome the long charging times associated with high inductance coils used in inductive discharge ignition (IDI) systems, making the ignition system more suitable for high engine speeds. The capacitive-discharge ignition uses capacitor discharge current to the coil to fire the spark plugs.

Signal edge

In electronics, a signal edge is a transition in a digital signal either from low to high or from high to low. It is called an edge because the square wave which represents a signal has edges at those points.

This is a subdivision of the Oscilloscope article, discussing the various types and models of oscilloscopes in greater detail.

This article discusses the history and development of oscilloscope technology. The modern day digital oscilloscope grew out of multiple developments of analog oscilloscopes, which in turn grew out of the older oscillograph. The oscillograph started as a hand drawn chart which was later slightly automated. This then grew into galvanometer driven recorders and photographic recorders. Eventually, the cathode ray tube came along and displaced the oscillograph, eventually taking over the majority of the market when advancements such as triggers were added to them. With the lowering costs of digital circuitry, the digital oscilloscope has taken over the majority of the modern oscilloscope sales, with almost no makers offering analog cathode ray tube oscilloscopes. However, the oscillograph lives on to a degree in pen chart recorders for electrical signals.

Digital signal signal that is constructed from a discrete set of waveforms of a physical quantity so as to represent a sequence of discrete values

A digital signal is a signal that is being used to represent data as a sequence of discrete values; at any given time it can only take on one of a finite number of values. This contrasts with an analog signal, which represents continuous values; at any given time it represents a real number within a continuous range of values.

Flip-flop (electronics) circuit that has two stable states and can be used to store state information

In electronics, a flip-flop or latch is a circuit that has two stable states and can be used to store state information. A flip-flop is a bistable multivibrator. The circuit can be made to change state by signals applied to one or more control inputs and will have one or two outputs. It is the basic storage element in sequential logic. Flip-flops and latches are fundamental building blocks of digital electronics systems used in computers, communications, and many other types of systems.

Digital storage oscilloscope

A digital storage oscilloscope is an oscilloscope which stores and analyses the signal digitally rather than using analog techniques. It is now the most common type of oscilloscope in use because of the advanced trigger, storage, display and measurement features which it typically provides.

A time base generator, or timebase, is a special type of function generator, an electronic circuit that generates a varying voltage to produce a particular waveform. Time base generators produce very high frequency sawtooth waves specifically designed to deflect the beam in cathode ray tube (CRT) smoothly across the face of the tube and then return it to its starting position.

Pico Technology manufacturer of PC-based oscilloscopes

Pico Technology is a UK-based manufacturer of high-precision PC-based oscilloscopes and automotive diagnostics equipment, founded in 1991. Their product range includes the PicoScope line of PC-based oscilloscopes, data loggers, automotive equipment, and most recently, handheld USB-based oscilloscopes. Since their inception in 1991, Pico Tech has been researching and developing PC-based oscilloscopes, when the market standard was analogue storage oscilloscopes. Pico Technology is one of two European scope manufacturers, and competes in the low to middle end of the instrumentation market.

PicoScope (software) oscilloscope software application

PicoScope is computer software for real-time signal acquisition of Pico Technology oscilloscopes. PicoScope is supported on Microsoft Windows, Mac OS X, Debian and Ubuntu platforms. PicoScope is primarily used to view and analyze real-time signals from PicoScope oscilloscopes and data loggers. PicoScope software enables analysis using FFT, a spectrum analyser, voltage-based triggers, and the ability to save/load waveforms to disk. PicoScope is compatible with parallel port oscilloscopes and the newer USB oscilloscopes.

Video line selector German term: an electronic diagnostic equipment for the precise evaluation of analog video signals

A video line selector is an electronic circuit or device for picking a line from an analog video signal. The input of the circuit is connected to an analog video source, the output triggers an oscilloscope, so display the selected line on the oscilloscope or similar device.