Jae-Chang Kwak and  Yong-Seo Koo,  The Design of PFM Mode DC-DC Converter with DT-CMOS Switch.   journal   = {International Journal of Energy and Power Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2014, vol. 91(7). 1167 - 1170
    [viewed 08 July 2020]. Available from: https://publications.waset.org/pdf/9999074.