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oe1(光电查) - 科学论文

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Power Efficient Current Driver Based on Negative Boosting for High-Speed Lasers

摘要： Vertical-cavity surface-emitting lasers (VCSELs) are commonly used in high-speed optical communication and 3D sensing applications. Both of these applications require high switching frequency and a short rise time of the VCSEL current. The parasitic inductance of the wire (connecting the driver with VCSEL) makes it challenging to achieve a short rise time, which often incur increased supply voltage and excessive power consumption. This paper utilizes a momentary boosting in supply voltage to overcome the parasitic inductance of the wire with minimal power overhead. The proposed technique uses a precalculated boosting capacitance to produce negative voltage for common-anode VCSELs. The boosting capacitance provides the required amount of charge during the rising transition and automatically disconnects itself in steady-state. Circuit simulations reveal up to three times shorter rise time at the negligible cost of less than 10% power overhead.

关键词： negative supply boosting,vertical cavity surface emitting lasers (VCSEL),switching circuits,CMOS laser drivers,pulsed laser diode driver

更新于2025-09-16 10:30:52
[IEEE 2019 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS) - Bangkok, Thailand (2019.11.11-2019.11.14)] 2019 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS) - Total Harmonic Distortion Adjustment Method and Circuit for LED AC Direct Driver IC

摘要： A novel scheme of total harmonic distortion (THD) adjustment for light-emitting diode (LED) alternating current (AC) direct driver integrated circuit (IC) is presented. The current flowing through the LED strings can be changed by using a plurality of THD adjustment modules and external resistors RTDs corresponding thereto. Consequently, the THD is adjusted. In addition, RTDs can be changed by users to achieve a small THD in different situations, like different AC power supply and different voltage drop distribution scheme of the LED strings. The proposed THD adjustment scheme is implemented in a 1μm high-voltage Bipolar-CMOS-DMOS process. Simulation results show that the proposed method can significantly reduce THD and is suitable for all types of cases.

关键词： LED AC direct driver IC,THD adjustment,different situation,external resistor,current

更新于2025-09-16 10:30:52
[IEEE 2019 International Symposium on Electromagnetic Compatibility - EMC EUROPE - Barcelona, Spain (2019.9.2-2019.9.6)] 2019 International Symposium on Electromagnetic Compatibility - EMC EUROPE - Modeling of conducted EMI noise in an Automotive LED Driver Module with DC/DC Converters

摘要： When transferring power from source to LED matrix, the electromagnetic interference (EMI) noise is generated. Moreover, the dc-dc converter with switching operation contains a wide range of harmonics. Therefore, it is important to predict the EMI noise in an automotive LED driver module. In this study, we firstly simulated conducted noise from the automotive LED driver module. The ringing noise of the dc-dc converter has been analyzed and simulated by using a circuit simulation. In order to simulate conducted EMI noise, parasitic components of power transfer line trace, passive components such as capacitor and inductor, active components such as diode and switching device, cable between PCB board and LED matrix, and connector in the LED driver module are considered. The simulation and measurement setup for conducted emissions are directed by CISPR 25 standard.

关键词： LED Driver,LDM,EMI,Conducted Emission,dc-dc Converter

更新于2025-09-16 10:30:52
Inductive decoupling-based multi-channel LED driver without electrolytic capacitors

摘要： Light-emitting diode (LED) drivers in outdoor street lighting applications suffer from short-lifetime because of the prolonged exposure to harsh environmental conditions such as high operating temperature, high humidity etc. A long-lifetime multi-channel LED driver consisting of front-end AC–DC boost power factor correction (PFC) converter followed by a DC–DC power conversion stage with dimming capability for LED-based street light is proposed in this study. This LED driver uses an inductor-based auxiliary decoupling circuit at the output of the AC–DC converter for mitigating the double-line-frequency power ripple present in the DC bus. The inductive ripple power storage circuit has a longer lifetime than a conventional capacitive storage circuit which is usually implemented by electrolytic capacitors. A digital control method is proposed to realise the decoupling control along with PFC control by a single non-digital signal processor micro-controller ST STM32F103RBT6. The proposed LED driver for street lighting is analysed and validated on a 150?W test setup. A comparison of active decoupling AC–DC converters for eliminating secondary-harmonic power ripple is displayed.

关键词： inductive decoupling,electrolytic capacitors,street lighting,LED driver,power factor correction

更新于2025-09-16 10:30:52
[IEEE 2019 International Aegean Conference on Electrical Machines and Power Electronics (ACEMP) & 2019 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM) - Istanbul, Turkey (2019.8.27-2019.8.29)] 2019 International Aegean Conference on Electrical Machines and Power Electronics (ACEMP) & 2019 International Conference on Optimization of Electrical and Electronic Equipment (OPTIM) - Highly efficient Multi-Junction Solar Cells Performance Improvement for AC Induction Motor Control Using the dsPIC30F Microcontroller

摘要： In-vehicle speech-based interaction between a driver and a driving agent should be performed without affecting the driving behavior. A driving agent provides information to the driver and helps his/her driving behavior and non-driving-related tasks, e.g., selecting music and giving weather information. In this paper, we focus on a method for determining utterance timings when a driving agent provides non-driving-related information. If a driving agent provides a driver with non-driving-related information at an inappropriate moment, it will distract his/her driving behavior and deteriorate his/her safety driving. To solve or to mitigate the problem, we propose a novel method for determining the utterance timing of a driving agent on the basis of a double articulation analyzer, which is an unsupervised nonparametric Bayesian machine learning method for detecting contextual change points. To verify the effectiveness of the method, we conduct two experiments. One is an experiment on a short circuit around a park in an urban area, and the other is an experiment on a long course in a town. The results show that the proposed method enables a driving agent to avoid inappropriate timing better than baseline methods.

关键词： Driving agent,machine learning,driving data,driver distraction,nonparametric Bayes

更新于2025-09-16 10:30:52
[IEEE 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - Harbin, China (2019.8.11-2019.8.14)] 2019 22nd International Conference on Electrical Machines and Systems (ICEMS) - A High Frequency Low Profile OLED Driver Based on GaN HEMTs

摘要： In this paper, a high frequency OLED driver circuit is proposed. Without choke inductors, the profile of the driver can be greatly reduced. Class Φ2 inverter is used to reduce the voltage stress of the switch while maintaining soft switching characteristics. The T-type network maintains a constant current output over a wide load range while the reflected impedance remains resistive. A 48V input 150mA output prototype based on GaN HEMTs was built to verify the feasibility of the proposed OLED driver circuit.

关键词： OLED driver,high frequency,matching network

更新于2025-09-16 10:30:52
[IEEE 2019 IEEE Energy Conversion Congress and Exposition (ECCE) - Baltimore, MD, USA (2019.9.29-2019.10.3)] 2019 IEEE Energy Conversion Congress and Exposition (ECCE) - A Multiplexing Off-Line LED Driver Achieves High Power Factor and Flicker-Free Operation

摘要： Although a single-stage off-line LED driver can achieve low cost and high efficiency, the notorious double-line-frequency flicker issue with a single-stage LED driver limits its usage in high-quality lighting applications. To solve lighting flicker, multiplexing operation is proposed in this paper. One switching cycle is further divided into two portions, namely phase one and phase two, which produces a main output voltage and an opposite ripple voltage. The main and the opposite ripple voltage are connected in series to form the LED voltage, which is a DC because of ripple cancellation. Therefore, a DC LED current can be produced and achieves flicker-free LED driving performance. A 7.5W experimental prototype had been built and tested to verify the design concept.

关键词： power factor correction,ripple cancellation,multiplexing operation,flicker-free,LED driver

更新于2025-09-12 10:27:22
[IEEE 2019 IEEE Energy Conversion Congress and Exposition (ECCE) - Baltimore, MD, USA (2019.9.29-2019.10.3)] 2019 IEEE Energy Conversion Congress and Exposition (ECCE) - Resonant Switched-capacitor Auxiliary Circuit for Active Power Decoupling in Electrolytic Capacitor-less AC/DC LED Drivers

摘要： This paper introduces an auxiliary circuit that is used to buffer double-line-frequency ripple power and form electrolytic capacitor-less single-phase AC/DC LED drivers. The proposed auxiliary circuit is implemented by a resonant switched capacitor circuit behaving as a gyrator circuit, namely a voltage-dependent current source. The output current of the auxiliary circuit is regulated with constant on-time and hysteresis control schemes. Comparing with other alternative methods, the proposed auxiliary circuit has less power loss due to its zero-current switching (ZCS) operation, and includes smaller passive components because of its higher operating frequency (about 3 MHz). An LED driver prototype with the proposed auxiliary circuit is built, and the experimental results are given to verify the proposed topology and the parameter design.

关键词： resonant switched-capacitor circuit,ac–dc power conversion,electrolytic capacitor less,LED driver,ripple power decoupling

更新于2025-09-12 10:27:22
[IEEE 2019 IEEE 10th International Symposium on Power Electronics for Distributed Generation Systems (PEDG) - Xi'an, China (2019.6.3-2019.6.6)] 2019 IEEE 10th International Symposium on Power Electronics for Distributed Generation Systems (PEDG) - An LED Driver with Adjustable Output Current

摘要： In many occasions, it is necessary to remotely adjust the brightness of the LED and monitor the working state of the LED driving power. Aiming at this goal, this paper designs an LED driver with adjustable output current. The main structure of the circuit adopts APFC+LLC. The driving power is internally equipped with a power measurement module and a relay switch module, and the external power supply is equipped with wireless control module. It can realize adjust the LED light, and can also monitor the power consumption, input voltage, input current, power factor, output voltage and output current of the driving power supply.

关键词： APFC,Adjustable output current,Electric energy measurement,LLC,LED driver

更新于2025-09-12 10:27:22
Adaptive Peak Average Current Control LED Driver for Automotive Lighting

摘要： This letter describes a new average current control dc–dc LED driver suitable for automotive pixel (matrix) lighting. Current is sensed only on an integrated high side switch and peak current is controlled to achieve required average output current independent of tolerances of components and parameters other than the current sensing itself. Fast reaction to output voltage changes required by the pixel light operation is achieved by using a constant ripple control with an off time inversely proportional to the output voltage.

关键词： Average current control,dc–dc LED driver,LED lighting,matrix light,pixel light

更新于2025-09-12 10:27:22

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