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What is transistor switching with clamped inductive load?
Transistor Switching having Clamped Inductive Load Power BJT. The delay in time during turn on or turn off is due to the time taken by the minority carrier to reach suitable density point. Its switching characteristics are specified in relation to external load circuit and the waveform for the base current.
What are inductive loads?
Reactive/Inductive Load – An inductive load converts current into a magnetic field. Inductive reactance resists the change to current, causing the circuit current to lag voltage. Examples of devices producing reactive/inductive loads include motors, transformers and chokes.
Is air conditioner an inductive load?
Inductive loads use magnetic fields (i.e., wire wound coil), as in a windlass, air conditioning unit, or blender. The general rule is, if it moves, it is probably an inductive load, which pulls a large amount of current (inrush current) when it is first energized.
Why is a clamped inductive load needed in a power supply?
This causes a HUGE voltage spike between the inductor and the transistor that is likely to exceed the voltage rating of the transistor and damage it. That is what the clamping diode is there to prevent: it will prevent that node between the inductor and the transistor from rising above the voltage of the power supply and damaging your transistor.
Why does a clamped inductive load resist V = IR?
The inductor does not like the current flowing through it to change: however many amps it is (0, 1, or 42), the inductor wants it to stay like that (due to storing energy as a magnetic field: you have to ‘charge up’ the magnetic field to increase current or ‘discharge’it to reduce current). It resists complying with V = IR.
Is the clamped inductive circuit driven by an ideal step?
The switching circuit with the clamped inductive circuit in the case of the power MOSFET is shown in Fig. 5. The gate is driven by an ideal step-voltage source. Also, diode is taken to be ideal and thus not showing any reverse recovery characteristics.
What happens when an inductive load is switched?
An inductive load pulls a large amount of current when first energized, then settles down to a full-load running current after a few seconds or cycles. When switched, inductive loads can cause excessive voltages.