This free eBook provides technical details and design considerations for implementing the common circuit board power management functions. This book also provides generalized cost effective solutions for each of these functions that can be customized to meet a circuit board’s specific voltage, current and control environment.

Every circuit board is powered from one or more sources called the input, or primary, power supplies. And, every circuit board performs one or more functions using a number of ICs, such as ASICs, CPUs, FPGAs, and so on. These ICs are called the payload ICs. The circuit board generates multiple power rails from the input supplies to power these payload ICs, using board mounted supplies called primary and secondary supplies. The term ‘Power Management’ in this book includes all power rail control functions implemented in a circuit board. Typically, input power rails are controlled by power management functions such as hot-swap control and redundant power rail control. On the payload side, power management functions include sequencing, monitoring, supervisory signal generation, trimming and margining.