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^ Oltage. Junction J2 breaks and starts conducting. A high value of changing current maydamage the SCR. SO SCR may be protected from high . 4. Temperature triggering During forward biased, J2 is reverse biased SO a leakage forward current always associated with SCR. Now as we know the leakage current is temperature dependant, so if we increase the temperature the leakage current will also increase and heat dissipitation of junction J2 occurs. When this heat reaches a sufficient value J2 will break and conduction starts. Disadvantages This type of triggering causes local hot spot and may cause thermal run away of the device. This triggering cannot be controlled easily.It is very costly as protection is costly. 5. Light triggering First a new recess niche is ade in the inner p-layer. When this recess is irradiated, then freecharge carriers (electron and hole) are generated. Now if the intensity is increased above acertain value then it leads First step is to choose a thyristor with forward breakover voltage (say 800V) higher than thenormal working voltage. The benefit is that the thyristor will be in blocking state with normal working voltage applied across the anode and cathode with gate open. When we require theturning ON of a SCR a positive gate voltage between gate and cathode is applied. The pointto be noted that cathode n- layer is heavily doped as compared to gate p-layer. So when gate supply is given between gate and cathode gate p-layer is flooded with electron from cathoden-layer. Now the thyristor is forward biased, so some of these electron reach junction J2 .As aresult width of 2 breaks down or conduction at J2 occur at a voltage less than VBO . As increases VBO reduces which decreases then turn ON time. Another important point isduration for which the gate current is applied should be more then turn ON time. This meansthat if the gate current is reduced to zero before the anode current reaches a minimum valueknown as holding current, SCR can't turn ONIn this process power loss is less and also low applied voltage is required for triggering. Line - frequency diodes: The on state voltage of these diodes is designed to be as low as possible and as a consequence have larger trr, which are acceptable for line frequency applications. These diodes are available with blocking voltage ratings of several kilovolts and current ratings of several kilo amperes. Moreover, they can be connected in series and parallel to satisfy any voltage and current requirement. How to test Diode? We know that fact that resistance of diode in forward biased condition is low and the resistance of diode in reverse biased condition is high. Keep the multimeter in the ohmmeter section. If we measure the resistance of a diode using the connections like red lead to anode and black lead(common) to cathode, a healthy forward biased diode will give low resistance. A high resistance reading in both directions indicates an open(defective device) condition, while a very low resistance reading in both directions will probably indicate a shorted device. Collision Resolution Random Number generator = ( 3 * address 1 ) % 19 1 How many probes for key 199645