Types Flashcards
Types
Rectifier Diode
Shotkey Diode
Zener Diode
LED’s
Under normal conditions a diode conducts current when it is
Forward Biased
Arrowhead points?
the direction of the diode symbol’s “arrowhead” points against the direction of electron flow
The term “diode” is customarily reserved for
small signal devices, I ≤ 1 A
The term rectifier is used for
power devices, I > 1 A.
Arrowhead points?
the direction of the diode symbol’s “arrowhead” points against the direction of electron flow
Facing out of Positive = allows current to flow
Facing out of negative = blocks current
The term rectifier is used for
power devices, I > 1 A.
forward-biased
polarity of the battery is such that electrons are allowed to flow through the diode
forward-biased
polarity of the battery is such that electrons are allowed to flow through the diode
Low voltage on diode means
high voltage through circuit
cathode on real component
stripe
Cathode
Postive N-type material
Anode
Negative P-type semiconductor
If Negitive terminal atached to poistive (N Type)
Forward Biased (Conductor)
The term kT/q describes
the voltage produced within the P-N junction due to the action of temperature, and is called the thermal voltage, or Vt of the junction
The term kT/q describes
the voltage produced within the P-N junction due to the action of temperature, and is called the thermal voltage, or Vt of the junction
voltage drop across a conducting, semiconductor diode
constant at 0.7 volts for silicon and 0.3 volts for germanium.
voltage drop across a conducting, semiconductor diode
constant at 0.7 volts for silicon and 0.3 volts for germanium.
The maximum reverse-bias voltage that a diode can withstand without “breaking down” is
called the Peak Inverse Voltage, or PIV rating.
How to Test diode
Switch to Ohm
Plug to Ohm
Cathode (Stripe) vs Postive = High resistance
Cathode (Stripe) vs Negative = Low resistance
rectification is
the conversion of alternating current (AC) to direct current (DC)
half-wave rectifier.
It only allows one half of an AC waveform to pass through to the load.
Half-wave rectification W
however, a very simple way to reduce power to a resistive load.
Half-wave rectification Application
Some two-position lamp dimmer switches apply full AC power to the lamp filament for “full” brightness and then half-wave rectify it for a lesser light output.
full-wave rectifier Setup
center-tap design
Left=VAC ,transformer
Right=Two diodes(Both same direction),a lead to base of Load and Load
full-wave rectifier ,1st half wave Current Flow
Left:starts cycling current
Right:Current flows through one diode only and then back through lead
full-wave rectifier ,2nd half wave Current Flow
Left:starts cycling current opposite direction
Right:Current flows through lead and then back through other diode only