Building blocks of modern embedded systems, including processors, SoCs, system DRAM, non-volatile memories, sensors, and connectivity modules, have varied power requirements. On one extreme, a system power management IC (PMIC) integrates all or almost all of the required power rails. On the other hand, individual power rails are implemented using d. The nature of the loads will determine how much power must be delivered and what, if any, special attributes are required from power sources. For example, power supplies to processor cores and hardware accelerators will require a good transient response and support for Dynamic Voltage and Frequency Scaling (DVFS) (i.e., the ability to adjust the vo. The semiconductor process and circuit design for implementing a low-Iq power supply for a sensor with very low duty cycle generally differs from those needed to produce DVFS power supply for a digital core. For example, the latter must offer software programmability and thus would be better to be implemented on a process which allows designers to e. Given that cost is almost always an important consideration when making design trade-offs, system designers would prefer to implement or pay for features only when necessary. Although a high-powered, all-in-one PMIC can save space and simplify hardware power design, it may not be the optimal solution for a particular use case. Unused features and e. The latest embedded systems utilize ultra-high clock frequencies to enhance system performance and increase processing power. Also, the speed of a circuit corresponds linearly to the supply voltage. However, when the system is not required to run at its highest performance, the supply voltage and clock frequency must be scaled down. DVFS functional.