Integrated regulation can reduce the effective supply impedance of digital circuits to meet the required supply noise margin with high efficiency. This can be achieved with a push-pull regulator topology in which the gain of regulation is controlled by digitally turning on sub push-pull blocks. The measured results from a 0.18 um CMOS test-chip verify that the proposed scheme reduces supply noise by similar to 25% for 10% noise budget and similar to 43% for 5% noise margin.