How snubber circuit working and what is the calculation?
Snubber circuit in any design works as a shock absorber. When we say shock absorber, in electrical circuit it is nothing but the transient voltages that are generated due to inductive loads or any switching circuits. For example if you have an inductive load, and when you apply sudden voltage, the inductor doesn't allow sudden change in current so there is a transient developed there before inductor starts conducting. This initial transient is nothing but an energy which need to be absorbed. The same applies to any switching circuits. For this a simple R-C circuit in parallel to inductor shall be used. The resistor can be selected by dividing the voltage by current desired. The capacitor selection is not straight forward. It depends on how often the switching happens in the circuit and the voltage applied. If the load switching happens at a Frequency F and voltage V is applied, the capacitor value can be 1/(V*V*F).
The snubber could be a diode as well. In that case, finding a diode is straight forward depending on current, forward drop, reverse recovery time.
---------------------------
It is a very broad topic and there are different kinds of snubbers. In short, snubbers are designed to limit di/dt or dv/dt due to a switching element in a power circuit. Read through the application note "slup100.pdf" available at TI website.
]]>
0 Comments