Current-source-mode single-inductor multiple-output LED driver with single closed-loop control achieving independent dimming function
File(s)second_jrnl.pdf (1.21 MB)
Accepted version
Author(s)
Dong, Z
Tse, CK
Hui, SYR
Type
Journal Article
Abstract
Single-inductor multiple-output (SIMO) LED drivers have the advantages of being compact, efficient and low cost. However, the voltage-to-current transfer function of each output of the SIMO converter is not independent, with significant cross regulation issues that necessitate the use of complex closed-loop control for achieving independent dimming function. This paper proposes a current-source-mode (CSM) SIMO dc-dc converter from duality principle, which is shown to be more suited for LED driving due to widened control range of the duty cycle and inherently inductor-less LED driving topology. The outputs of the CSM SIMO dc-dc converter are inherently independent, resulting in very simple control requirement involving only one closed-loop controller for providing the constant current feeder, and several simple open-loop controllers for independent dimmable driving of LEDs. Simultaneous voltage step-up and step-down of multiple outputs is an added feature that simplifies the input power source requirement especially for portable applications. The whole system is simple, reliable and low cost. Taking the CSM single-inductor dual-output (SIDO) dc-dc converter as an example, we illustrate the circuit operation and establish a small-signal model for facilitating the design of the feedback control. A direct duty-cycle dimming method is described. Experimental tests are presented for verification.
Date Issued
2018-09-01
Date Acceptance
2018-04-01
Citation
IEEE Journal of Emerging and Selected Topics in Power Electronics, 2018, 6 (3), pp.1198-1209
ISSN
2168-6777
Start Page
1198
End Page
1209
Journal / Book Title
IEEE Journal of Emerging and Selected Topics in Power Electronics
Volume
6
Issue
3
Copyright Statement
© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Publication Status
Published
Date Publish Online
2018-04-30