Transcript A CMOS-Control Rectifier for Discontinuous Conduction Mode
A CMOS-Control Rectifier for Discontinuous Conduction Mode Switching DC-DC Converters ISSCC 2006 / SESSION 19 / ANALOG TECHNIQUES / 19.8 Tsz Yin Man, Philip K.T. Mok and Mansun Chan Class presentation: Davood Amerion University of Tehran 28 December 2006 Preliminary Power Supply topology 1- isolated - Push-pull (Half/full bridge) - Fly back 2- non isolated - Buck converter - Boost converter - Buck-Boost converter Boost Converter  Operating modes  : - Discontinuous current mode - Continuous current mode MOTIVATION • The power efficiency and inductor profile of switching dcdc converters are two of the most important issues in modern battery powered mobile systems. • Discontinuous-conduction mode (DCM) operation enables both a reduction in the switching losses and the use of a small inductor in the high switching frequencies (10s to 100s of MHz). • In this paper, a CMOS-Control Rectifier (CCR) is proposed to simultaneously provide adaptive dead time control and mV-range forward-voltage drop for sub-1V highly efficient DCM switching dc-dc converters employed in single cell battery-powered mobile systems. CCR diagram  Results  • Technology 0.35μm 2-poly 4-metal CMOS technology. • 1μH inductor. • comparators in the proposed CCR facilitates nanosecond response times, TON (~20ns) and TOFF (~60ns) • the proposed CCR provides mV-range forward-voltage drop and the conduction loss is significantly lower than silicon or Schottky diodes • regulated output voltage of 2.5V with 100mA maximum output current. The input voltage range is from 0.9 to 1.2V. • a 4.7μF output capacitor and a 1μH inductor are used to facilitate the application of the entire boost converter to modern pocket-size, or even thumb-size, mobile systems. • Maximum power efficiency of ~ 87% is achieved at 100mA output current and 1.2V input voltage. References: •  ISSCC 2006 / SESSION 19 / ANALOG TECHNIQUES / 19.8 Tsz Yin Man, Philip K.T. Mok and Mansun Chan •  Texas instrument: understanding boost power stage in switchmode power supply application report, march 1999, SLVA061 Any question?