2 Modes of Operation
Figure 1. Interleaved Boost Basic Diagram
The mode of operation can be analyzed based on one channel. Since both power channels share current
and because both inductors are identical, each power channel behaves identically. Based on the amount
of energy that is delivered to the load during each switching period, the boost converter can be classified
into continuous or discontinuous conduction mode. If all the energy stored in the inductor is delivered to
the load during each switching cycle, the mode of operation is classified as discontinuous conduction
mode (DCM). In this mode the inductor current ramps down to zero during the switch off-time. If only part
of the energy is delivered to the load, then the converter is said to be operating in continuous conduction
mode (CCM). Figure 2 shows the inductor current waveforms for both modes of operation.
The mode of operation is a fundamental factor in determining the electrical characteristics of the
converter. The characteristics vary significantly from one mode to the other.