Power Intent Formats

The October blog about CPF, UPF 1.0, and IEEE 1801 power domain definitions resulted in some reader feedback and suggestions. Several points are worthy of further discussion and clarification. Let me start with the toughest questions. What is my motivation behind the blog? Am I trying to make CPF look better than UPF/IEEE 1801? My preferred choice of power intent should not be a surprise ... » read more

Power Intent Formats: Isolation

By Luke Lang Last month, I discussed power domain for all three power formats: CPF, UPF 1.0, and IEEE 1801. I mentioned isolation but mainly used it to explain power domain. This month’s blog will address isolation in detail. First, isolation cells are required at off-to-on domain crossings. When a domain is shut off, all of its output nets become undriven. If these floating nets drive direct... » read more