PMP20818 is a holdup reference design that uses the LM3481 non-synchronous boost and LM5141-Q1 synchronous buck controllers. When the 12V input supply is available, the buck converter is disabled, and the boost converter charges a capacitive holdup bank. In the event of a power outage, the boost converter is disabled, and the buck converter is enabled to holdup the 12V input rail for 15ms with a load of 12.5A.
- Boost followed by synchronous buck
- Peak current-mode control
- Buck turns on automatically at input power loss
- No user control required
- Low dropout buck maximizes holdup time