Triangular Mode
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SNIU028A – February 2016 – Revised April 2016
Copyright © 2016, Texas Instruments Incorporated
Digital Pulse Width Modulator (DPWM)
As seen later, the Filter module has two outputs, Filter Duty and Filter Period. In the Resonant mode, the
Filter is configured so that the Filter Period is twice the Filter Duty. With zero dead times, each DPWM pin
would be On for half of the period. For dead time handling, the average of the two dead times is
subtracted from the Filter Duty for both DPWM pins. Therefore both pins will have the same on-time, and
the dead times will be fixed regardless of the period. The only edge which is fixed relative to the start of
the period is the rising edge of DPWM A. Blanking A and Blanking B both work only on DPWMA.
2.7
Triangular Mode
Triangular mode provides a very stable phase shift in interleaved PFC and similar topologies. In this case,
the PWM pulse is centered in the middle of the period, rather than starting at one end or the other. In
Triangular Mode, only DPWM B is available. Here is a diagram for Triangular Mode:
Figure 2-8. DPWM – Triangular Mode