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.

Analysis and design of a triangular active charge injection for stabilizing resonant power supply noise

“…In order to meet this demand of the smaller capacitance, we designed the canceling capacitor circuit by using [8] through the parasitic inductor and resistor. The switching transistors are activated complementarily by the injection controller circuit discussed above.…”

“…In order to detect a resonant power supply noise drop in one clock cycle, we designed an on-chip votage drop detector based on the voltage drop sensor discussed in [8].…”

“…As the transistor size and delay become smaller and the operational frequency increases, not only an IR drop but also a resonant power supply noise make it difficult to realize robust operations of our LSI chips due to parasitic inductance on the power supply line [1]- [8]. A resonant power supply noise is caused with parasitic inductance and circuit capacitance when the amount of current consumption is rapidly changed due to the operation mode change, for example, and it has large noise level as well as long duration time as shown in Fig.1.…”