China International Forum on Solid State Lighting 

About: China International Forum on Solid State Lighting is an academic conference. The conference publishes majorly in the area(s): Light-emitting diode & LED lamp. Over the lifetime, 526 publications have been published by the conference receiving 791 citations.

Comparison and analysis of short circuit capability of 1200V single-chip SiC MOSFET and Si IGBT

Abstract: Short circuit capability of commercial SiC MOSFETs is analyzed, which is compared with that of commercial Si IGBTs. Junction temperatures during short circuit tests are analyzed in this work. A test bench is designed for short circuit tests of discrete MOSFETs and IGBTs. Commercially available 1200V SiC MOSFETs from Wolfspeed (C2M0080120D) and 1200V Si IGBTs from Infineon (IKW25N120H3) with similar current rating are tested. The short circuit withstand time (t cr ) of the 1200V SiC MOSFET is much shorter than that of the 1200V Si IGBT. A 1-D transient finite element thermal model based on structure parameters is constructed to investigate the junction temperature curves during short circuit. According to the analysis of heat generation, short circuit capability of the SiC MOSFET is mainly restricted by high electric field at the P-N junction and high short circuit current density.

5G Internet of radio light services for supermarkets

Abstract: In this paper we present a 5G Internet Radio-Light (IoRL) architecture for supermarkets that can be readily deployed because it utilizes unlicensed visible light and millimeter wave part of the spectrum and which is used to provide shoppers with accurate location, interaction, access to Internet and Cloud based services such as high resolution video on a Tablet PC. The paper describes the supermarket use cases, the user and functional requirements and the IoRL architecture.

34.5 m Underwater optical wireless communication with 2.70 Gbps data rate based on a green laser with NRZ-OOK modulation

Abstract: This study proposed and experimentally demonstrated a high-speed long-distance underwater optical wireless communication (UOWC) system using a 520 nm green laser diode (LD) with non-return-to-zero on-off keying (NRZ-OOK) modulation scheme. The UOWC link offers maximum data rates up to 4.60 Gbps, 3.93 Gbps, 3.48 Gbps and 2.70 Gbps over the underwater distances of 2.3 m, 11.5 m, 20.7 m and 34.5 m with the bit-error rates below the forward error correction (FEC) criterion of 3.8 χ 10−3. To the best of our knowledge, UOWC data rate of 2.70 Gbps at 34.5 m is the highest at present.

Reliability and lifetime prediction of LED drivers

Abstract: LED drivers are critical components in LED luminaires, which power and control LEDs to deliver light as desired. They are also the weakest links inside LED luminaires so that their lifetime can greatly affect the useful life of the whole system. Therefore, the study on the reliability and lifetime of LED drivers is of great theoretical significance and practical value. This paper presented two methods to predict the reliability and lifetime of LED drivers. One method is an improved part stress analysis method based on MIL-HDBK-217F without the need of conducting reliability testing, the other is an experiment-based method using accelerated life testing. The paper also applied both of the methods to predict the lifetime of the same quasi-flyback LED driver. The temperature-dependent lifetime results are demonstrated in the paper, and a good match between the two sets of results was observed. This indicates the improved part stress analysis method presented in this work is an effective way to predict the reliability and lifetime of LED drivers. Also, the method is especially suitable for the reliability and lifetime research in the course of designing and developing LED luminaires because it does not require reliability testing which is typical expensive and time-consuming.

Influence of AlGaN back barrier layer thickness on the dynamic ron characteristics of AlGaN/GaN HEMTs

Abstract: AlGaN back barrier with different thickness is used in AlGaN/GaN high electron mobility transistors (HEMTs) to evaluate the device performances. It shows that a proper AlGaN back barrier thickness (t bb ∼100 nm) is beneficial for obtaining low leakage current and high Ion/Ioff ratio of approximately 108. While further increasing the AlGaN thickness can deteriorate the device performances because of the generation of more surface defects. The dynamic on-resistance (RON) degradation measurements demonstrate that the proper AlGaN back barrier thickness (tbb) can not only improve the 2DEG confinement, but also prevent electrons penetrating into buffer layer. Thus, it results in the reduction of trapping effect and then the improvement of dynamic R ON .