Near-threshold SIDO DC-DC converter with a high-precision ZCD for phase change memory chip

This letter proposes a near-threshold single-inductor double-output (SIDO) DC-DC converter with a high-precision zero current detector (ZCD) circuit which supply voltage to phase change memory (PCRAM) chip in wireless sensor network. It has a specific startup procedure to provide wide input voltage range. And the ZCD circuit is designed according to volt-second balance theory and minimizes the duration of reverse inductor current to about 1 nS. The DC-DC converter is implemented in 110 nm standard CMOS process and the maximum power efficiency is 89.47% with no cross regulation.