SNIU028D February 2016 – September 2020 UCD3138 , UCD3138064 , UCD3138064A , UCD3138128 , UCD3138A , UCD3138A64
In most modes, it is possible to synchronize multiple DPWM modules using the phase shift signal. The phase shift signal has two possible sources. It can come from the Phase Shift Register or from the Filter Duty value.
The Phase Shift Register provides a fixed value, which is useful in simple multiphase systems such as interleaved PFC.
When the Filter Duty is the source, the changes in the filter output cause changes in the phase relationship of two DPWM modules. This is useful for phase shifted full bridge topologies if voltage mode control is desired rather than peak current mode.
Figure 2-5 shows the mechanism of phase shift: