This paper presents a scalable single-input-multiple-output DC/DC converter targeting load transient response and security improvement for low-power System-on-Chips (SoCs). A two-stage modular architecture is introduced to enable scalability. The shared switched-capacitor pre-charging circuits are implemented to improve load transient response and decouple correlations between inputs and outputs. The demo version of the converter has three identical outputs, each supporting 0.3V to 0.9V with a maximum load current of 150mA. Based on post-layout simulation results in 32nm CMOS process, the converter output provides 19.3V/μs reference tracking speed and 27mA/ns workload transitions with negligible voltage droops or spikes. No cross regulation is observed at any outputs with a worst-case voltage ripple of 68mV. Peak efficiency reaches 85.5% for each output. With variable delays added externally, the input-output correlations can change 10 times and for steady-state operation, such correlation factors are always kept below 0.05. The converter is also scaled to support 6 outputs with only 0.56mm2 more area and maintains same load transient response performance.

2022 IEEE International Symposium on Circuits and Systems (ISCAS)