Special Purpose Diodes
- What is a Zener diode, and how do Zener breakdown and avalanche breakdown differ? In one line A Zener diode is a heavily doped silicon p-n junction diode designed to work safely in reverse breakdown, where its voltage stay... 1
- How does a light emitting diode produce light, and what decides the colour of an LED? In one line An LED is a forward-biased p-n junction in which electrons recombine with holes and release their energy as photons; the colour... 1
- What does the V-I characteristic of a Zener diode look like and what do its key points mean? In one line The Zener V-I characteristic is like a normal diode in forward bias, but in reverse bias the current stays almost zero until V_Z... 1
- What is the internal structure of an LED and why does it need a series resistor? In one line An LED is a p-n junction chip with a thin top layer for light to escape, mounted in a reflector cup inside a transparent epoxy l... 1
- How does a Zener diode work as a voltage regulator against changes in input and load? In one line In a Zener shunt regulator, a series resistor drops the extra input voltage while the Zener diode, connected in reverse across t... 1
- How are LEDs used in indicator lamps and seven-segment and dot-matrix displays? In one line LEDs are used as indicator lamps to show the status of a device and are arranged as segments or dot grids to display digits, let... 1
- How are LEDs used for lighting, and why are they replacing incandescent and CFL lamps? In one line White LEDs, usually a blue LED chip coated with yellow phosphor, are used in bulbs, tubes, street lights, vehicles and display b... 1
- Draw and explain the construction diagram of LED and enlist the applications. LED (Light Emitting Diode): a PN junction diode that emits light when forward biased (electroluminescence). Made of direct band-gap compound... 1
- Explain the application of Zener diode as a voltage regulator. Zener diode as a voltage regulator (shunt regulator). Rs I_L +o---/\/\/---+--------+ ^ I -> | | | I_Z | R_L V_o = V_Z Vin _|_ cathode up | |... 1
- Explain working of a LED. LED (Light Emitting Diode): a PN junction diode that emits light when forward biased (electroluminescence). Made of direct band-gap compound... 1
- Draw the characteristics of Zener diode and Explain application of a Zener diode as a voltage regulator Zener diode: a heavily doped silicon PN junction diode designed to operate in the reverse breakdown region without damage. Symbol: diode wit... 1
- Write applications of LED. Applications of LED: Indicator / pilot lamps on electronic equipment, panels and chargers. Seven-segment and dot-matrix displays (calculator... 1
- Draw and explain the V-I characteristics of a Zener diode Zener diode: a heavily doped silicon PN junction diode designed to operate in the reverse breakdown region without damage. Symbol: diode wit... 1