高效车用HID灯控制解决方案

英飞凌推出基于XC864的低成本插入式子板,用于控制适用于35W车用HID灯的标准位电子镇流器.子板通过高速峰值电流控制方法实现了最佳的灯功率调节,确保高效无噪运行.先进的保护功能包括短路保护、开路保护和输入过压保护.     

电源

飞兆半导体推出高集成度镇流器芯片；Microchip 0．5A小型MOSFET驱动器；研诺推出12V降压DC／DC转换器；盛群超低启动电压的升压型DC／DC转换器；奥地利微电子推出低电压／低门限值的微处理器监控电路；     

数字控制金卤灯电子镇流器样机设计

本文基于金卤灯电子镇流器数字控制策略分析的基础上,对其电路拓扑的主电路和控制电路进行设计,即对PFC、DC/DC、DC/AC三级结构的主电路及控制电路模型和参数进行选择、设计,并研制了一台高功率因数低频方波输出的数字控制金卤灯电子镇流器,通过对实验结果分析验证了所提出的数字控制方案是可行的。     

车载电子镇流器故障诊断电路的设计与研究

市场上的车载前照灯HID灯电子镇流器一般无故障诊断功能,给维修和整车故障诊断带来麻烦.针对这一现象,提出了一种具有较高的可靠性和实用性,且成本低廉的故障诊断电路设计方案.该方案软件部分用来诊断故障的类型,即无故障,输入过压或欠压,输入过流,HID灯过流或过压,硬件部分根据故障的类型给出不同的输出直流电压电平.经PSPICE仿真分析和样灯测试表明,其电平最大误差控制在2.5％范围内,方便了维修和整车故障诊断.     

Si8500：交流电流传感器

Silicon Laboratories推出耗电少、精确度高及适合各种电源应用的交流电流传感器。Si8500系列可为电源系统的控制与保护功能提供高达20A的电流测量能力，最适合AC／DC交换式电源供应、隔离式DC／DC电源供应、马达控制和照明设施电子镇流器等各种应用。[第一段]     

电源

低压微处理器监测芯片；高度集成、双／四通道CCFL控制器；用于镇流器和LCD的PFC控制IC；可支持24个LED的3通道LED镇流器；600mA、同步升／降压型DC／DC转换器     

数字式荧光灯电子镇流器的研究与设计

荧光灯由于其复杂的启动过程和时序控制要求,传统的模拟控制实现往往显得麻烦且复杂.介绍了一种基于数字控制的通用化荧光灯电子镇流器,它以MC56F8013 DSP作为控制核心,采用Boost电路进行功率因素校正.通过变频控制,实现了荧光灯预热,高压启动与调光功能.与传统模拟电子镇流器相比,该电子镇流器结构简单,控制灵活并易...     

有源功率因数校正控制电路的设计

有源功率因数校正控制器主要应用于电子镇流器、LED灯驱动和AC/DC电源中。本文结合当前先进照明电源的要求,实现了微功耗启动,并且有静态电流和工作电流小、功耗低的特点,可以方便地使芯片工作在省电模式。本设计采用内置乘法器,使功率因数在大的输入电压以及负载范围内接近于1。本电路设计了动态和静态两种过压保护机制,能安全处理启动和负载断开时产生的过电压。同时根据该类型电路的应用特点,增加了很多保护功能,保证各类照明驱动电源安全稳定地工作。     

C波段固态功率放大器

Aethercomm公司推出了一种高功率C波段功率放大器，工作频率为5．0GHz～6．2GHz．25℃下1dB增益压缩(P1dB)功率最大值为20W．25℃下的饱和输出功率典型值为25W，输入／输出电压驻波比(VSWR)最大值为2．0：1。其标准性能是反向极性保护、输出短路与开路保护、集成DC／DC变换器具有过压和欠压保护。该器件还配有合适的DC开关电路，     

基于PIC16F883的锂电池智能充电器的设计与实现

设计了一个具有充放电功能的锂电池充电器,充电电路采用数字控制的Buck变换器,放电电路采用高效率的集成Boost变换器。充电器采用DC/DC拓扑结合脉冲充电控制的充电方案。系统以集成了多种外围模块的PIC16F883单片机作为控制核心,控制电路简洁有效,具备对锂离子电池进行过充、过放和过温保护的功能。     

Novel Design of HID Lamp Electronic Ballast for Automotive Systems

This paper presents a high intensity discharge（HID） lamp for automotive illumination. A novel type of ballast for HID is proposed without an acoustic resonance. The system consists of high frequency DC/DC converter,DC/AC inverter（SLA2403M）, high voltage igniter and a microcontroller unit（MCU）. The proposed ballast controls the complex start-up process and constant power process by programming on the rnicrocontroller. It is verified that experimental results agree well with the calculated ones. The ballast features such functions as failure protection, line under-voltage, line over-voltage, output short circuit and disconnection protections.     

A high-frequency electronic ballast for HID lamps based on aλ/4-long distributed constant line

A novel type of solid-state ballast, which operates in the megahertz-range frequency, is presented in this paper. A circuit composed of a voltage-source half-bridge inverter, a distributed constant line and a parallel LC resonant circuit has been developed for this purpose. The high-intensity discharge (HID) lamp is connected to the output terminal of the inverter through the distributed constant line. Here, since the length of the line is adjusted to 1/4 of the propagation wavelength λ (λ/4 condition), the output voltage of the voltage-source inverter can be converted to a current source on the load side. Therefore, the ballast can supply not only high voltage to the HID lamp for initiating discharge, but also stable current to it during discharge condition. The modification of the proposed circuit is also proposed in order to expand the operating frequency without increasing the undesirable harmonic current. The experimental results from a prototype system verify the theoretical procedure     

Analysis and Improvement of Automotive High Intensity Discharge Lamp Ballast Based on Microcontroller Unit

The superior performance of high intensity discharge（HID） headlamp is clearly shown for luxury sedans, and the lamp luminescence properties are analyzed. The principle of its ballast technology is analyzed in detail. For against the disadvantage of current ballast technology for sedans lamp, a novel type of electronic ballast for HID is designed based on programmable intelligent computer（PIC） microcontroller unit（MCU） and S1A2410M inverter and it provides guidance and can be easily used in control configuration selection and design. The feasibility and superiority of the system are proved.     

A microcontroller-based emergency ballast for fluorescent lamps

This paper presents a new emergency ballast for fluorescent lamps. The fundamental block is the microcontroller-based control circuit, which performs the supervision and control function. High-frequency electronics techniques are proposed for the high power factor battery charger and the lamp driver, which provides high luminous efficacy. In this way, size and weight have been minimized for the whole system. With the introduction of the microcontroller, the system has the capability of testing itself, checking its functional state, and displaying internal faults. Thus, the reliability of the system is improved and, concurrently, maintenance cost is decreased     

高精度双通道红外图像采集与VGA显示系统的设计

为了更好地满足红外图像处理系统对高精度图像采集与处理的需求，本文设计了10bit量化精度的视频采集与显示系统，选用10bit TVP5147视频解码芯片和ADV7123型视频编码芯片为核心器件，提供两路10bit数字视频输出、一路10bit数字视频输入的TTL／LVDS接口，以及一路CVBS外同步信号输出，由1片ATmega16L单片机和3片XC95144XL CPLD器件分别实现视频编／解码芯片的在线配置和接口逻辑控制。寄存器配置程序具有人机界面，通过PC的串口完成对TVP5147主要寄存器的配置。在CPLD中采用Verilog硬件描述语言设计10bit的YUV空间到RGB空间的实时色域转换功能模块，以实现系统VGA模拟显示的功能。实验表明，该系统有效克服了传统8bit空间转换中由于二次取整数而存在的带状线和轮廓线的缺陷，具有通用性好、灵活性好、功耗低和精度高等特点，完全可以满足图像融合、目标识别等图像处理应用系统的要求。     

Design and analysis of automotive high intensity discharge lamp ballast using micro controller unit

A new scheme of the automotive high intensity discharge (HID) lamp ballast systems is proposed. The proposed scheme is consisted of the high frequency DC-DC converter and the low frequency DC-AC inverter as same as conventional HID ballast system. However this system separates the input voltage of the ignitor from DC link voltage using auxiliary winding, which results in the use of the lower voltage rating power devices for HID lamp ballast system compared with conventional system. As a result, proposed system has a lower cost or a higher efficiency. For the improvement of the efficiency, the proposed ballast controller using micro-controller unit (MCU), controls the frequency to operate the DC-DC converter in critical conduction mode. This paper presents the design and analysis of the proposed ballast and some experimental results.     

A Modified Valley Fill Electronic Ballast Having a Current Source Resonant Inverter With Improved Line-Current Total Harmonic Distortion (THD), High Power Factor, and Low Lamp Crest Factor

In this paper, a modified valley fill (VF) circuit is employed to combine with a current-fed resonant inverter as a passive high power factor (PF) electronic ballast. A conventional VF circuit limits the line current to conduct when the conduction angles are: 30deg les omegat les 150deg and 210deg les omegat les 330deg during the line period, which results in high total harmonic distortion (THD). The modified VF circuit has the following advantage: When the capacitors are connected in parallel, the voltage across the capacitors is one-third of the peak voltage, which allows the conduction angle of the line current to be further extended to 19.5deg les omegat les 160.5deg and 199.5deg les omegat les 340.5deg, so that a lower THD can be achieved. The high lamp crest factor (CF) problem generated by the high ripple voltage from the modified VF circuit is improved in the proposed ballast as variable frequency control is employed to continuously regulate the lamp current. An experimental prototype is then built in the laboratory to verify the feasibility of the proposed work for a 26-W compact fluorescent lamp. The final results confirm that a PF of 0.986 and a lamp CF of 1.49 are achieved with the proposed circuit, whereas a PF of 0.96 is achieved with the conventional VF ballast.     

Novel Automotive High Intensity Discharge(HID) Lamps with Electronic Ballasts

A new scheme of automotive high intensity discharge(HID) lamps with electronic ballasts is proposed. The design of the proposed ballast and some experimental results are presented. The proposed scheme is consisted of the high frequency DC-DC converter and the low frequency DC-AC inverter. This system separates the input voltage of the ignitor from DC link voltage using auxiliary winding, then it could use the lower voltage rating power devices for HID lamp ballast system and reduce the size of HID lamp ballast. The proposed ballast controller using micro-controller unit(MCU) controls the frequency to operate the DC-DC converter in critical conduction mode, which reduces the noise of the circuit and improves the efficiency by 2%~4%.     

High performance series-parallel type on-line UPS

An improved single-phase uninterruptible power supply (UPS) is proposed that is composed of a series converter and a parallel converter. The series converter regulates the output voltage, and then the parallel converter provides reactive current compensation and battery charging. A fast detection technique of the line voltage is proposed, which has almost zero transition time from the line power mode to the power failure mode. Furthermore, a current controller of the parallel converter for unity power factor is suggested and it is derived using the feedback linearization technique. A current limit technique in the power failure mode is proposed to protect the parallel converter without a system trip under any impulsive load. All control algorithms are implemented in software with a single-chip microcontroller. Experimental results obtained under a 3?kVA prototype show good transient and steady-state performance such as almost negligible transition time, 97% power efficiency and 99% power factor.     

Development of a distributive control scheme for fluorescent lighting based on LonWorks technology

In this paper, a new distributive control system for indoor fluorescent lighting based on LonWorks technology is presented. The system features the following elements: microprocessor-controlled fluorescent lamp electronic ballast, communication system using the power line as communication media, and control software for Windows 95 environment. The electronic ballast has been especially designed to be operated under the proposed distributive control system. Thus, it features high-input power factor, high-frequency lamp supply, lamp power regulation against line voltage variations, dimming capability, and lamp failure detection. With this scheme, a low-cost distributive control system for lighting applications has been achieved, allowing energy and maintenance savings and increase in the reliability of the fluorescent lighting systems.