An energy efficient high-speed digital LED driver for visible light communications

Author

Jalajakumari, Aravind V.N. ; Cameron, Katherine ; Henderson, Robert ; Tsonev, Dobroslav ; Haas, Harald

Author_Institution

Institute for Integrated Micro and Nano Systems, The University of Edinburgh, UK, EH9 3JL

fYear

2015

fDate

8-12 June 2015

Firstpage

5054

Lastpage

5059

Abstract

In this paper an energy efficient light emitting diode (LED) driver circuit for visible light communications (VLC) and results from the electrical and optical characterization are presented. A current steering digital to analogue converter (DAC) based LED driver circuit supporting 4-channels with an 8-bit resolution is realized in a 0.18 µm complimentary metal oxide semiconductor (CMOS) technology. Each channel delivers a full-scale current of 255 mA and achieves up to 67% electrical efficiency when driving 250 MS/s orthogonal frequency division multiplexing (OFDM) signals. Optical differential drive capability is demonstrated by using two output branches of a single channel to drive two different LEDs with an SNR improvement (>5 dB). The chip is also capable of full digital control of color shift keying (CSK) using multi-color LEDs enabling lighting color-temperature adjustment, dimming and multiple-input and multiple-output (MIMO) optical communications and these aspects will be the subject of future research.

Keywords

Clocks; Current measurement; Field programmable gate arrays; Light emitting diodes; OFDM; Semiconductor device measurement; Signal to noise ratio; CMOS LED driver; OFDM; digital to analogue converter; visible light communications;

fLanguage

English

Publisher

ieee

Conference_Titel

Communications (ICC), 2015 IEEE International Conference on

Conference_Location

London, United Kingdom

Type

conf

DOI

10.1109/ICC.2015.7249125

Filename

7249125