Dynamic voltage scaling in hierarchical multi-tier regulator supply

An apparatus comprising:

• a plurality of voltage regulators, each configured to generate a dynamically-adjusted supply voltage, comprising:
• a set of external switching voltage regulators comprising respective switching voltage regulators for at least two analog voltage domains, the set of external switching voltage regulators located off-chip;
• a local linear voltage regulator connected to a corresponding switching voltage regulator and configured to generate the dynamically-adjusted supply voltage for at least a portion of the analog voltage domain of the respective switching voltage regulator, the local linear voltage regulator located on-chip;
• a plurality of analog circuits subdivided into groups of analog circuits, the plurality of analog circuits grouped based on voltage supply requirements over a plurality of test corners, each group configured to receive one of the dynamically-adjusted supply voltages;
• and
• for each group of analog circuits, a corresponding monitoring circuit representative of said group of analog circuits, the corresponding monitoring circuit configured to provide a control signal indicative of a measured performance of said group of analog circuits, the control signal used in adjusting the received dynamically-adjusted supply voltage.