SNIU028D February 2016 – September 2020 UCD3138 , UCD3138064 , UCD3138064A , UCD3138128 , UCD3138A , UCD3138A64
For an overview of what these registers do, see Section 2.11. There are 4 Auto Switch threshold registers:
DPWMAUTOSWIHIUPTHRESH
DPWMAUTOSWIHILOWTHRESH
DPWMAUTOSWILOUPTHRESH
DPWMAUTOSWILOLOWTHRESH
These registers are used in topologies which dynamically switch from one DPWM mode to another, such as Phase Shifted Full Bridge and LLC. They control which one of three registers sets many of the DPWM control bits. There are 4 registers so that each of the 2 dividing lines can have hysteresis.
The three registers are:
DPWMCTRL0
AUTOCONFIGMID
AUTOCONFIGMAX
If the Filter input to the DPWM goes above DLWMAUTOSWIHIUPTHRESH, then the AUTOCONFIGMAX register is used until the Filter input goes below the DPWMAUTOSWIHILOWTHRESH register value.
Below this value the AUTOCINFIGMID control bits are used, until the Filter value goes below DPWMAUTOSWILOLOWTHRESH. Below this value, DPWMCTRL0 is used.
Mode switching is enabled by setting the AUTO_MODE_SEL bit in DPWMCTRL1. Making the waveforms transition smoothly across the mode switching boundary can be complex.