1. lecture 131 Maximum Power Transfer (4.4) Prof. Phillips February 28, 2003

2. lecture 132 Maximum Power Transfer To obtain the maximum power transfer from a fixed source to a variable load, the load resistance (R L ) is chosen equal to the Thevenin equivalent resistance representing the remainder of the network R L = R Th

3. lecture 133 Maximum Power Transfer v oc R Th RLRL R L = R Th +–+– What is the amount of power transferred?

4. lecture 134 Amount of Power Transferred Since R L = R Th, then by using voltage division, one can easily see that the voltage across both R L and R Th is half of v oc So half of the power is dissipated in the load The other half is “lost” to the source

5. lecture 135 Class Example