Measurement of worst-case power delivery noise on chip under operating conditions

Maximum power delivery noise is a major indicator of chip performance. The measurement of the worst-case noise is technically difficult because maximum possible noise might not be achieved in a typical chip operation and creating a special stimulus generating this noise might push the chip beyond its operational margin. The paper considers an approach in which extraction of the absolute maximum power delivery noise of the operating chip does not require generation of a special stimulus. The measurement is conducted for controlled periodic computer process with step-wise changing computer activity. Measurement of computer activity variation is also discussed