An Area-Efficient and Low-Power Digital Pulse-Width Modulation Controller for DC-DC Switching Power Converter

In this paper, a low-power digital controller for DC-DC power conversion was presented. The controller generates the pulse-width modulated (PWM) signal from digital inputs provided by analog-to-digital converter (ADC). An efficient and simple design scheme to develop the control unit was discussed. This method allows minimization of the consumed resources of the chip and it is based on direct digital design approach. In this application, with the proposed scheme, nearly half area and two-third of the power consumption was saved compared to the conventional schemes. This work illustrates the possibility of implementing low-power and area-efficient power management circuit using direct digital design based approach. 

• Jingjing Lan
• Jun Zhou
• Xin Liu

• Buck converter
• DC-DC power conversion
• digital control
• proportional-integral (PI) controller.

[1] D. Maksimovic and R. Zane, “Small–signal discrete–time modeling of
digitally controlled PWM converters,” IEEE Trans. Power Electron.,
vol. 22, no. 6, pp. 2552–2556, Nov. 2007.
[2] M. M. Peretz and S. Ben-Yaakov, “Time-domain design of digital
compensators for PWM DC–DC converters,” IEEE Trans. Power
Electron., vol. 27, no. 1, pp. 284–293, Jan. 2012.
[3] G. Wei and M. Horowitz, “A low power switching power supply for
self-clocked system,” in Proc. IEEE Int. Symp. Low Power
Electron.Design, Monterey, CA, 1996, pp. 313–317.
[4] Y.-F. Liu, E. Meyer, and X. Liu, “Recent developments in digital control
strategies for DC/DC switching power converters,” IEEE Trans. Power
Electron., vol. 24, no. 11, pp. 2567–2577, Nov. 2009.
[5] A. Prodic and D. Maksimovic, "Digital PWM Controller and Current
Estimator for a Low-Power Switching Converter,” in The 7th Workshop
on Computers in Power Electronics 2000. COMPEL 2000, Blacksburg,
VA, 2000, pp. 123 - 128.
[6] A. Peterchev, J. Xiao, and S. Sanders, “Architecture and IC
implementation of a digital VRM controller,” IEEE Trans. Power
Electron., vol. 18, no. 1, pp. 356–364, Jan. 2003.
[7] K. H. Ang, G. Chong, and Y. Li, “PID Control System Analysis, Design,
and Technology,” IEEE Trans. Control Systems Technology, vol. 13, pp.
559 - 576, July 2005.