Power integrity

Power integrity or PI involves a series of electronic engineering efforts aimed at ensuring that power supply subsystems adequately support the performance of an entire electronic system.

PI engineering focuses on designing and evaluating power supply subsystems to prevent any degradation in system performance due to potential adverse effects from the power supplies. For instance, a noisy power supply can cause audible or visible disturbances or slow down data communication. PI engineering employs various methods to minimize or eliminate such noise. The effectiveness of PI engineering is measured by the overall system performance, even though it specifically addresses power supply circuits. In other words, PI engineering identifies circuit blocks that are sensitive to power supply perturbations and requires careful attention.

PI is essential for achieving successful signal integrity (SI) engineering, which deals with impedance matching among multiple elements. Like SI, PI also ensures proper connections between a power supply and a load device, which is often a concern for SI. This connection path is known as a power delivery network (PDN), and tuning the PDN path from the power source to load devices is referred to as PDN impedance design.