Diodes Flashcards
The purpose of a diode is to _____. This characteristic of the diode is described as changing _____ to ______.
The purpose of a diode is to allow current in one direction and stop current in the other direction. This characteristic of the diode is described as changing AC current flow to DC current flow.
What is th reference designator for a diode?
The reference designator for a diode is CR or D.
The ____ diode schematic symbol is an arrow (triangle) and bar.
The junction diode schematic symbol is an arrow (triangle) and bar.
Which side of the arrow represents the positive and negative sides? What are these sides called?
The arrow represents the positive side of the diode, called the anode.
The bar represents the negative side of the diode, called the cathode.
The arrow and bar are generally marked on the diode. If not, what is used at one end that will indicate the cathode side?
A dot or band will indicate the cathode side.
Diodes are also marked with identification numbers. What do these numbers/letters mean?
The 1 indicates a diode.
The N indicates the component is solid state.
The last digits identify the type of diode.
Which diode looks like the junction diode but with with two flags?
Zener Diode
Zener diodes are special purpose diodes designed to regulate _______.
Zener diodes are special purpose diodes designed to regulate voltage.
Which diode uses the junction diode symbol with the addition of two small arrows?
Light Emitting Diodes (LEDs)
LEDs are designed to give off light when current flows through the device.
Why would a diode be used as a rectifier?
Used in power supplies to convert AC voltages to pulsating DC voltages.
The diode allows current flow in one direction, which produces a pulsating DC voltage.
The filter and voltage regulator are added to the circuit to produce a pure DC output.
Why would a diode be used as a limiter?
To remove signal voltages above or below a specific level.
Limiters are like rectifiers, except they are useful in signal shaping and typically used at frequencies much greater than 60 Hz.
What type of diode adds a DC level to the AC input?
Clamper Diode
The junction diode is represented pictorially by a rectangle containing an ____ and ____ side.
The junction diode is represented pictorially by a rectangle containing an N and P side.
The schematic symbol for the junction diode is an arrow and bar. The arrow represents ____ and the bar represents____.
The schematic symbol for the junction diode is an arrow and bar. The arrow represents P and the bar N.
The junction diode is constructed from two materials called ______. What is the purpose of these materials?
The junction diode is constructed from two materials called N-type and P-type.
The N material has electrons free to move while the P material has holes free to move. They are attracted toward each other.
The material used to construct a junction diode stops current flow in the other direction.
What is a forward biased diode?
A diode is forward biased when the negative terminal of the voltage source is connected to the N-type material and the positive terminal of the voltage source is connected to the P-type material.
What is a reverse biased diode?
A diode is reverse biased when the negative terminal of the voltage source is connected to the P-type material and the positive terminal of the voltage source is connected to the N-type material.
What happens when the diode is placed in a circuit and is forward biased?
The negative terminal repels electrons toward the junction.
The force of the battery helps electrons cross the junction or barrier region, producing current flow.
When the diode is placed in a circuit and reverse biased, what is happening in the depletion area.
The depletion area becomes larger.
Electrons are unable to cross the barrier region and current flow is effectively stopped.
Which circuit is a forward biased diode?
