Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group
  • Journal of Display Technology
  • Vol. 8,
  • Issue 3,
  • pp. 162-165
  • (2012)

Comparison of the EMI Performance of LED PWM Dimming Techniques for LED Video Display Application

Not Accessible

Your library or personal account may give you access

Abstract

Light-emitting diode (LED) video displays enclose thousands of LEDs which create the resulting image. LED intensity is regulated using pulse width modulation (PWM). Though the individual LED current is small, the total current consumed is large. Simultaneous switching of a large number of LEDs dimmed by PWM can cause serious electromagnetic interference (EMI). Three LED PWM dimming techniques have been studied for potential EMI. Techniques represent different current pulse positioning in time: the aim of study was to compare the spectrum of current produced in LED video display power supply circuits when discussed techniques are used for pixel intensity control. It was assumed that the produced EMI is proportional to the power supply current. The power supply filter and transient load decoupling capacitors were not taken into account. The uniform and nonuniform pixels' intensities distribution within an image were assumed. Spectrum has been studied on a single pixel and the video display tile containing 16×32 LEDs. Resulting time diagrams and frequency responses are presented. The results indicate that, despite expected significant advantage of binary PWM methods, in realistic case all methods' performance is similar.

© 2012 IEEE

PDF Article
More Like This
Reverse polarity optical-OFDM (RPO-OFDM): dimming compatible OFDM for gigabit VLC links

Hany Elgala and Thomas D. C. Little
Opt. Express 21(20) 24288-24299 (2013)

Performance of dimming control scheme in visible light communication system

Zixiong Wang, Wen-De Zhong, Changyuan Yu, Jian Chen, Chin Po Shin Francois, and Wei Chen
Opt. Express 20(17) 18861-18868 (2012)

Full-color micro-LED display based on a single chip with two types of InGaN/GaN MQWs

Zhou Wang, Shijie Zhu, Xinyi Shan, Zexing Yuan, Xugao Cui, and Pengfei Tian
Opt. Lett. 46(17) 4358-4361 (2021)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved