J4 ›› 2012, Vol. 39 ›› Issue (2): 181-185.doi: 10.3969/j.issn.1001-2400.2012.02.030

• Original Articles • Previous Articles     Next Articles

Crest factor over-current protection circuit in the electronic ballast

SHI Lingfeng1,2;CAO Chengmei1,2;REN Juanli1,2;KANG Hui1,2   

  1. (1. Inst. of Electronic CAD, Xidian Univ., Xi'an  710071, China;
    2. Ministry of Education Key Lab. of High-Speed Circuit Design and EMC, Xidian Univ., Xi'an  710071, China)
  • Received:2011-05-03 Online:2012-04-20 Published:2012-05-21
  • Contact: SHI Lingfeng E-mail:lfshi@mail.xidian.edu.cn

Abstract:

A crest factor over-current protection circuit is presented. The resistance of the low-side drive tube is used to realize resonant inductor current sampling and  crest factor measurement is taken to obtain over-current protection. The circuit is completed on over-current protection for different resonant inductors, so that it extends the work time of electronic ballasts. Typically in the 0.5μm BCD(Bipolar, CMOS, DMOS) process, Hspice simulation results show that the designed circuit can accurately realize over-current protection for the resonant inductor.

Key words: crest factor over-current protection, current sample, low-pass filter

CLC Number: 

  • TP13