J4 ›› 2010, Vol. 37 ›› Issue (3): 476-480+506.doi: 10.3969/j.issn.1001-2400.2010.03.016

• Original Articles • Previous Articles     Next Articles

Design of a low input voltage startup circuit for the Boost DC-DC converter

CHEN Fu-ji;LAI Xin-quan;LI Yu-shan;YE Qiang;YUAN Bing   

  1. (Research Inst. of Electronic CAD, Xidian Univ., Xi'an  710071, China)
  • Received:2009-01-09 Online:2010-06-20 Published:2010-07-23
  • Contact: CHEN Fu-ji E-mail:fjchen@126.com

Abstract:

This paper presents a startup circuit for a low voltage Boost DC-DC converter. Firstly, the DC-DC converter is started in the open loop, and then the converter is powered by the output port for normal operation. Secondly, the minimum voltage of the circuit is as low as 1.5V. Thirdly, the quiescent current of the VIN Pin is small. Finally, the circuit is designed and implemented by UMC 0.6μm BCD technology. Experimental results demonstrate that DC-DC can be started up in an input voltage greater than or equal to 1.5V. The quiescent current of the VIN is only 18μA. With VIN=1.5V and VOUT=7V, the peak current of the inductor is 2A.

Key words: DC-DC Boost, low voltage, startup circuit