Figure 7-19 below describes the theory of operation for multiphase DCAP+ control, in continuous conduction mode (CCM).

The summed inductor currents, I_SUM, and output voltage deviation information, along with appropriate gain and integration, are processed to form a control signal V_COMP. Neglecting the output voltage information and integration, the V_COMP signal is a scaled version of I_SUM. A compensating ramp signal, V_RAMP, has a slope proportional to the number of phases, and switching frequency setting. When the V_RAMP and V_COMP signals intersect, the controller fires a new pulse.

Phase management logic distributes new pulses to the next phase in the firing order sequence. Each phase is assigned a firing order, at which pulses are passed to that phase. A separate, slower loop adjusts the on-times for each phase based on the output voltage setpoint, switching frequency setting, and current balance error.

Figure 7-19 DCAP+ conceptual diagram (FCCM)

Figure 7-20 DCAP+ conceptual diagram (DCM)