All power processors presented so far carry a common trait; the output voltage is less than the input, that is, step–down.
Occasions arise from time to time that the input is low voltage battery sources, but outputs higher than the source are needed. In that case, step–up, that is, boost processors are called for. In theory, flyback converters given in Part II can perform both step–down and step–up. But issues of control mechanism tend to constrain its applications in step–down.
In this part, topology specifically configured to act in step–up operation is covered. Voltage-mode control is first presented, then current-mode follows.
Since the scope of this writing is not intended for basics, readers who need to refresh the procedure ...