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From graphics processor units (GPUs) and central processing units (CPUs) to field-programmable gate arrays (FPGAs), digital signal processors (DSPs), and heterogeneous SoCs, every processor requires power sequencing. These digital loads often operate from multiple voltage rails, each of which may supply a different on-chip power domain. Power sequencing is the process of applying and removing power from these voltage rails in a specific order during system startup and shutdown.

If the appropriate sequencing isn’t followed, the function of the load may be limited and defective. Also, in extreme cases, the load can be destroyed. To prevent this, sequencing functions are employed.