A 10A/μs Fast Transient AOT Voltage Regulator on DDR5 DIMM with Dithered Pseudo-Constant Switching Frequency Achieving -6dB Harmonic Suppression

Abstract

The on-board voltage regulator in the DDR5 memory module is required to resiliently supply current at large load transient events and alleviate output noise at the same time. We present an adaptive on-time (AOT) buck regulator with a turbo dual-phase interleaving logic for stable regulation and on-time control with dithered pseudo-constant switching frequency to suppress output harmonics by 6dB. The voltage regulator delivers up to 10A with a peak efficiency of 92.5% and covers 10A/μs steep load transients.