Resonant power supply noise cancelling with noise detector based in DLL and vernier TDC

Abstract

This paper proposes an active resonant power supply noise cancelling with fast voltage drop sensor using the combination of delay-locked loop (DLL) and vernier time-to-digital converter (TDC). Also, we propose the capacitor selector circuit realizing the active insertion of capacitors in less silicon area. These components enable one clock noise detection with fine resolution. Simulation results show that our noise sensor detects 54 mV voltage drop in one clock cycle and cancels 28% of the supply noise by the active charge injection. The proposed circuits use the silicon area about 27 times more effectively than conventional passive decaps.