Electronics and Power Supply Practice Flashcards

Comprehensive vocabulary flashcards covering semiconductor types, diode biasing, energy bands, Zener diodes, power supply components, BJTs, SCRs, and DIACs.

N-Type Semiconductor

A semiconductor where pentavalent (5e- valence) impurity atoms are added to increase the number of electrons.

P-Type Semiconductor

A semiconductor where trivalent (3e- valence) impurity atoms are added to increase the number of holes.

Donor Atom

A pentavalent atom often called this because it gives up an electron.

Pentavalent Impurity Atoms

Atoms such as Arsenic, Phosphorus, and Antimony used to create n-type material.

Trivalent Impurity Atoms

Atoms such as Boron and Indium used to create p-type material.

Forward Bias

A condition where the anode is connected to the positive terminal and the cathode to the negative, typically requiring $0.7\,V$ for forward current to increase rapidly.

Reverse Bias

A condition where the cathode is connected to the positive terminal and the anode to the negative, resulting in reverse current.

Depletion Region

A region formed at the pn junction during formation where electrons diffuse and combine with holes, creating a barrier of positive and negative charges.

Barrier Potential

The potential created across the depletion region that acts as a barrier to avoid further movements of electrons through the junction.

Semiconductor

An electrical material that is neither a good conductor nor a good insulator.

Insulator

An electrical material that does not conduct electric current and has a large energy gap between the valence and conduction bands.

Conductor

An electrical material where the conduction and valence bands overlapped, allowing current to flow easily.

Zener Current ($I_Z$)

Also called reverse current, this current remains small until the 'knee' of the curve and then increases rapidly after breakdown.

Zener Impedance ($Z_Z$)

Also known as internal Zener resistance, it begins to decrease as the reverse current increases rapidly.

Rectifier

A component in a basic power supply that converts AC voltage to pulsating DC voltage.

Filter

A circuit designed to eliminate fluctuations in rectified voltage to produce smooth DC voltage.

IC Regulator

A circuit that maintains a constant DC voltage despite variations in the input line voltage.

BJT Cut off State

A condition where both BE and BC junctions are reverse biased, resulting in zero currents and $V_{CE(cut\,off)} = V_{CC}$.

Common Emitter Configuration

A type of BJT configuration where the emitter is connected to the ground terminal.

Silicon Controlled Rectifier (SCR)

A device with an anode, gate, and cathode used as a latching switch in power control.

Anode Current Interruption

A method for turning off an SCR by reducing $I_A$ to zero via series or shunt interruption.

Forced-commutation

A method to turn off an SCR using a circuit consisting of an npn transistor, a pulse generator, and a DC battery.

Holding Current ($I_H$)

The minimum amount of current required to hold a DIAC in its conducting state.

DIAC

Diode for Alternating Current; primarily used in power control circuits to provide a trigger pulse for a triac.

Step-down Regulators

A specific type of DC to DC power supply.

Inverters

DC to AC converters that provide AC output at main frequency from a battery source, often used for stand-by supplies.