Adaptive on-chip power supply with robust one-cycle control technique

ABSTRACT

In this paper, an integrated adaptive output switching converter is proposed. The design uses a one-cycle control for fast line regulation and a single outer loop for load regulation and fine tuning. A switched-capacitor integrator is introduced in the one-cycle control to obtain positive integration with a single positive power supply, allowing a standard low-cost CMOS fabrication process. To improve the efficiency, a dynamic loss control technique is presented. HSPICE Simulations are performed with transistor models from TSMC 0.35μm N-well CMOS fabrication process. With a supply voltage of 3 V, a voltage ripple of less than 15 mV is measured. The maximum efficiency is 92% with a load power of 475 mW. The converter exhibits a tracking speed of 2 μs/V for both start-up and reference voltage transitions. The recovery time for a 20% load change is approximately 2.6ms. The overall design exhibits superior system robustness to battery perturbations, noise and process variations.

REFERENCES

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.1 CONTROL STRUCTURES AND MICROPROGRAMMING

Additional Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
  B.8 Performance and Reliability

General Terms:
Design, Performance

Keywords:
adaptive output, one-cycle control, robust design, switching converter