"A"
"B"
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"
'Va' to 'Vd' 'Ve' to 'Vh' 'Vi' to 'Vz'
VIA. A plated-thru hole in a printed wiring board. A via may exist between one or more adjacent board layers, or through the entire board. A blind via runs vertically between the top [or bottom] side and through one or more adjacent board layers, but not through the entire board. A buried via runs between one or more adjacent internal layers, but does not run to the top or bottom layer. Also refer to Thermal Via. [PWB Design].
| VIA STUB. the portion of the via that is not in series with the signal. When a signal pin does not traverse the entire via, or when the signal layer using the via is not the bottom layer of the PWB. Two methods may be used to over come a via stub; Counter Boring, and Blind Vias, in both cases the via is terminated at its destination and not allowed to continue to the other side of the PWB. |
 Vias on a PCB |
VIBRATION. The oscillation of an element of a mechanical system about a set point.
VIDEO AMPLIFIER. An amplifier designed to amplify the entire band of frequencies from 10 hertz (10Hz) to 6 megahertz (6 MHz). Also called a Wide-Band Amplifier, or Video Line Driver. Related; Manufacturers of Video Interface ICs.
Video Amplifier
The normal impedance for a video amplifier is 75 ohms.
VIDEO ENHANCEMENT FEATURES. Similar to Anti-Jamming Circuit
[Radar Dictionary].
VINCULUM. A straight horizontal line placed over one or more members of a compound logic expression to negate or complement. Also, used to join two or more members together.
VIRTUAL GROUND. A point in a circuit that is at ground potential (0 V) but is not connected to ground.
VISIBLE SPECTRUM. The portion of the electromagnetic spectrum that can be seen. The visible spectrum extends between 0.37um to 0.75um. Refer to the Optical Spectrum Chart
VOICE COIL. A coil attached to the speaker cone [diaphragm] of an electromagnetic speaker. Read more on Manufacturers of Speakers.
VOICE FREQUENCY. The frequency range of the human voice ranging from 32Hz to around 16KHz. Note that telephone lines only transmit voice between 300Hz to 3500Hz.
VOICE OVER INTERNET PROTOCOL (VoIP). A technology for communicating using “Internet protocol” instead of traditional analog systems. Read more on VoIP.
VOLATILE MEMORY. A type of memory circuit that does not retain its data after power is removed. Volatile memory are primarily the RAM style memory. Read more on Manufacturers of Volatile Memory ICs.
VOLT. The unit of electromotive force or electrical pressure. One volt is the pressure required to send 1 ampere of current through a resistance of 1 ohm.
VOLTAGE. The term used to signify electrical pressure. Voltage is a force that causes current to flow through an electrical conductor. The voltage of a circuit is the greatest effective difference of potential between any two conductors of the circuit.
VOLTAGE AMPLIFIER. An amplifier in which the output-signal voltage is greater than the input-signal voltage.
VOLTAGE BREAK-DOWN. The voltage magnitude required to cause insulation failure.
VOLTAGE COMPARATOR. A circuit used to compare one or more voltages to another voltage. Typically a voltage comparator is accomplished by an Operation Amplifier, normally just called a comparator. Also refer to IC comparator manufacturers.
VOLTAGE CONTROLLED OSCILLATOR. [VCXO] An oscillator that uses a external voltage to tune or change the frequency of the oscillator's output. Also refer to Voltage Controlled Oscillator Manufacturers.
VOLTAGE DEPENDENT RESISTOR. Refer to the Varistor Definition.
VOLTAGE-DIODE DETECTOR. A series-diode detector in which the diode is in series with the input voltage and the load impedance.
| VOLTAGE DIVIDER. A series network in which desired portions of the source voltage may be tapped off for use in the circuit. Resistors R1 and R2 form the voltage divider, with the tapped point being between the two resistors. A voltage divide could consist of a number of different components, another common voltage divider could be formed by two capacitors in series. A Potentiometer could be used as a voltage divider by applying an input to the two ends and taking the output from the center tap and one end. Shunt Resistor applied to a Potentiometer. |
 R1/R2 Voltage Divider |
VOLTAGE DROP. The difference in voltage between two points. It is the result of the loss of electrical pressure as a current flows through a resistance.
VOLTAGE-FEED METHOD. Same as End-Feed Method [Antenna Dictionary].
VOLTAGE GAIN. The ratio of output voltage to input voltage in an amplifier.
VOLTAGE MULTIPLIERS. Methods of increasing voltages; used primarily where low current is required.
VOLTAGE REGULATION. A measure of the ability of a generator or power supply to maintain a constant output voltage from no-load to full-load operation. Expressed as a percentage of full-load voltage; the better the regulation, the lower the percent. [IC Voltage Regulators]
VOLTAGE STANDING WAVE RATIO (VSWR). In a waveguide, the ratio of the electric field (voltage) at a maximum point to that of an adjacent minimum point.
VOLTAIC CELL. A combination of materials used to convert chemical energy into electrical energy. A voltaic or chemical cell consists of two electrodes made of different types of metals or metallic compounds placed in an electrolyte solution
VOLTMETER. A meter used to measure voltage. [Test Equipment Manufacturers]
