Saved Bookmarks
| 1. |
A Zener of power rating 1 W is to be used as a voltage regulator. If zener has a breakdown of 5V and it has to regulate voltage which fluctuated between 3V and 7V, what should be the value of R_(s) for safe operation (See figure)? |
|
Answer» Solution :`P=V_(Z)I_(Z)` `THEREFORE (P)_("max.")=V_(Z)(I_(Z))_("max.")""(because V_(Z)=` CONSTANT) `therefore 1 = 5xx(I_(Z))_("max")` `therefore (I_(Z))_("max".)=(1)/(5)=0.2A` Here `v_(i)=I_(Z)=R_(S)+V_(Z)` `therefore (V_(i))_("max".)=(I_(Z))_("max.")R_(S)+V_(Z)` `therefore 7=0.2R_(S)+5` `therefore R_(S)=(7-5)/(0.2)=(2)/(0.2)=10Omega` |
|