fundamentals of analog circuits

Power supply

a device that converts ac or dc voltage into a voltage or current suitable for use in various applications to power electronic equipment. The most common form is to convert ac from the utility line to a constant dc voltage.

Varactor

a diode that is used as a voltage-variable capacitor.

Photodiode

a diode whose reverse resistance changes with incident light.

Clamper:

a circuit that adds a dc level to an ac signal; also called a dc restorer

Semiconductor

a material that has a conductance value between that of a conductor and that of an insulator. Silicon and germanium are examples.

Hole

a mobile vacancy in the electronic valence structure of a semiconductor. A hole acts like a positively charged particle

Germanium

a semiconductive material

Full-wave rectifier

a circuit that converts an alternating sine wave into a pulsating dc voltage consisting of both halves of a sine wave for each input cycle

Silicon

a semiconductive material used in diodes and transistors.

Crystal

a solid in which the particles form a regular, repeating pattern

Covalent bond:

a type of chemical bond in which atoms share electron pairs

Integrated circuit (IC)

a type of circuit in which all the components are constructed on a single tiny chip of silicon

Half-wave rectifier

a circuit that converts an alternating sine wave into a pulsating dc voltage consisting of one-half of a sine wave for each input cycle

Limiter

a circuit that removes part of a waveform above or below a specified level; also called a clipper.

Light-emitting diode (LED):

a type of diode that emits light when there is forward current.

Zener diode

a type of diode that operates in reverse breakdown (called zener breakdown) to provide voltage regulation.

Center tap:

a connection at the midpoint of the secondary of a transformer

Filter:

a type of electrical circuit that passes certain frequencies and rejects all others

Energy

the ability to do work

Bias

the application of dc voltage to a diode or other electronic devices to produce a desired mode of operation

Depletion region

the area near a pn junction on both sides that has no majority carriers

Electron

the basic particle of negative electrical charge in matter

PN junction

the boundary between n-type and p-type materials.

Load regulation

the change In output voltage for a given change in load current, normally expressed as a percentage.

Line regulation

the change in output voltage for a given change in line (input) voltage, normally expressed as a percentage.

Reverse bias:

the condition in which a pn junction blocks current.

Forward bias

the condition in which a pn junction conducts current

Barrier potential:

the inherent voltage across the depletion region of a pn junction

Recombination

the process of a free electron in the conduction band falling into a hole in the valence band of an atom

Doping

the process of imparting impurities to an intrinsic semiconductive material in order to control its conduction characteristics

Voltage regulation

the process of maintaining an essentially constant output voltage over variations in input voltage or load

Electroluminescence

the process of releasing light energy by the recombination of electrons in a semiconductor

Ion

an atom that has gained or lost a valence electron resulting in a net positive or negative charge.

Valence electron

an electron in the outermost shell or orbit of an atom

Conduction electron:

an electron that has broken away from the valence band of the parent atom and is free to move from atom to atom within the atomic structure of a material; also called a free electron

Rectifier

an electronic circuit that converts ac into pulsating dc.

Regulator

an electronic circuit that is connected to the output of a rectifier and maintains an essentially constant output voltage despite changes in the input, the load current, or the temperature.

Diode:

an electronic device that permits current in only one direction

Shell

an energy level in which electrons orbit the nucleus of an atom.

Terminal

an external contact point on an electronic device.

Discrete device:

an individual electrical or electronic component that must be used in combination with other components to form a complete functional circuit

Intrinsic (pure)

an intrinsic semiconductor is one in which the charge concentration is essentially the same as a pure crystal with relatively few free electrons

Cathode: (semiconductor diode definition)

the terminal of a diode that is more negative with respect to the other terminal when it is biased in the forward direction

Anode: (semiconductor diode definition)

the terminal of a semiconductor diode that is more positive with respect to the other terminal when it is biased in the forward direction

Ripple voltage

the variation in the dc voltage on the output of a filtered rectifier caused by the slight charging and discharging action of the filter capacitor.