1. suggests, on a certain current it regulates

1. Identify the types of diodes.The Following are types of Diodes:• Small Signal DiodeCommonly used for low current high frequency applications.• Large Signal DiodeLike the small signal diode but can handle higher current.• Zener DiodeActs like a normal diode but operates in reverse.• Light Emitting Diode (LED)It transforms electrical to light energy.• Constant Current DiodesAs the name suggests, on a certain current it regulates voltage.• Schottky DiodeUsed in fast switching applications.• Shockley DiodeLike the thyristor it has 4 layers which is PNPN.• Step Recovery DiodesA special diode also called snap-off diode and has its cut off frequency set to 200-300Ghz• Tunnel DiodeLike the schottky diode it is used for fast switching • Varactor DiodeAlso called as varicap, it is like a variable capacitor but operates in reverse.• Laser DiodeLike the LED but used in more complex applications like fiber optics.• Transient Voltage Suppression DiodeOperates like a normal diode but provides low impedance• Gold Doped DiodesInstead of normal doping chemicals the element used in doping is gold which is more sensitive than the other ones. • Super Barrier DiodesLike the schottky diode but can handle higher power applications.• Peltier DiodeUsed mainly for heating application which can be used as a sensor.• Crystal DiodeA type of contact diode which operates through contact.• Avalanche DiodePassive type of diode that is designed to be less damageable due to its operation.• Silicon Controlled RectifierLike the Shockley diode for small applications.• Vacuum Diodes• Old technology on which the other diodes where originated.• PIN DiodeConsists of heavily doped regions mainly used for ohmic contacts.• Point Contact DevicesCan act as insulator when reversed and acts like a normal diode in forward direction.• Gunn DiodeUses only N type material that produces RF signal.2. Discuss, illustrate and derive the related equations of various rectifier circuits.• Half Wave RectificationSchematic: Over the half of a full cycle which is the called the positive half cycle, the diode is in forward direction thus allowing the signal to pass through. On its negative half cycle the diode is considered as open thus blocking the signal.Input and Output waveform: Equations:? Output voltage:Vdc = 0.318 Vm (Ideal)? Output voltage with drop:Vdc 0.318(Vm – VK)? PIV Rating:PIV rating ? Vm• Full- Wave Rectification (Bridge Network)Schematic: For the positive half cycle the signal enters D2 and D3. For the negative cycle the diodes D1 and D4 conduct wherein the polarity in the resistor is the same resulting in a second positive half. Input and Output waveform: Equations:? Output voltage:Vdc = 0.636 Vm (Ideal)? Output voltage with drop:Vdc 0.636 (Vm – VK)? PIV Rating:PIV ? Vm• Full-Wave Rectification (Center-Tapped)Schematic: During the positive half cycle D1 is short and D2 is open. The flow of current is shown in the figure: During the positive half cycle D2 is short and D1 is open. The flow of current is shown in the figure: Input and Output waveform: Equations:? PIV:PIV ? 2Vm3. Discuss the block diagram of a power supply. You may illustrate it and the corresponding waveforms.Block Diagram of a power supply: The first step in a power supply is the transformer which takes the AC signal directly from an outlet:  From the primary coil runs the AC signal and it is being stepped down (commonly) to a lower AC signal with respect to the number of turns or simply its ratio.The second step is rectification; the ac signal is then transformed to a purely positive pulsating signal: The process is done by diodes connected in a certain configuration.After rectification comes the filter which is usually in the form of a capacitor. The filtration outputs a dc voltage with ripple: After the filter the signal is then regulated usually by an IC(78xx) or in basic applications a zener diode. The signal is then regulated to a pure dc signal.  The output DC voltage of the power supply is then delivered to a load.4. State other applications of a diode. (rectifier circuit is an application of diode)Other applications of Diode:-Clamp -Clippers/Limiters-Multiplier-Diode Logic-Standby Voltage-Gate-Reverse Current Protection-Voltage Spike Suppression-Bypass diodes in solar panels