低成本降压型大功率LED驱动芯片设计

发布时间：2018-04-13 19:54

本文选题：LED驱动 + 调光技术　；参考：《电子科技大学》2014年硕士论文

【摘要】：随着半导体行业高速发展,第三代电光源LED半导体照明技术应运而生,LED相对于传统电光源具有光效高、寿命长、环保等特点,吸引了业内外人士的广泛关注,政府也给予了对LED产业的支持相关政策。随着LED照明技术的不断进步,市场范畴的不断扩大,LED驱动IC行业也得到了高速发展。本文在研究LED驱动电路原理及发展方向的基础上,结合市场需求与工艺参数极限,本文设计了一款连续电感电流降压型LED恒流驱动芯片。该芯片采用高端电流采样设置LED平均电流,并可以通过DIM端口进行模拟调光和较宽范围的PWM调光;内部REGULATOR模块对输入电压进行稳压,产生内部供电电源,这样可以在不增加芯片面积成本的条件下,大幅度增大了输入电压范围;同时芯片内部集成有过温保护、欠压锁定等模块,确保系统能够安全稳定的工作。电路利用Cadence设计工具,将电路搭建在某公司0.35μm 40V BCD工艺平台下进行仿真验证及后端版图设计。本文首先选择对基准电压源、调光功能、欠压锁定等子模块进行分析与验证,确保每个模块在不同环境下都能稳定工作;接着对系统功能及规格参数进行仿真验证;最后完成版图设计。仿真验证结果表明:输入电压范围为8~30V,当输入电压低于4.5V时,功率管关断;调光电压范围为0.35~2.5V,当调光电压小于0.3V时,功率管关闭;输入电压在8~30V范围内变化时,输出电流变化仅仅为11mA,输出电流精度高达97%;在不同的调光环境下,调光误差均控制在3%内。该芯片具有高精度的输出电流、高的调光线性度、大的输出电流、成本低等优点。
[Abstract]:With the rapid development of the semiconductor industry, the third generation of electric light source LED semiconductor lighting technology came into being, LED compared with the traditional electric light source with high luminous efficiency, long life, environmental protection and other features, has attracted wide attention outside the industry, the government also gives policy support to LED industry. With the development of LED lighting technology, market category the expanding LED driver IC industry has also been rapid development. Based on the principle of LED driver circuit and the direction of development, combined with market demand and technological parameters of the limit, this paper introduces the design of a continuous inductor current step-down constant current LED driver chip. The chip uses a high current sampling set LED and average current. Through the DIM port analog dimming and a wide range of PWM dimming; internal REGULATOR module voltage to the input voltage, internal power supply, it can not The increase in chip area cost, greatly increases the input voltage range; at the same time chip integrated over temperature protection, undervoltage lockout module, ensure that the system can work safely and steadily. The circuit design using Cadence tools, the circuit simulation and layout design of a company in 0.35 m 40V BCD process under the platform. This paper first choice of reference voltage source, dimming function, undervoltage lockout module analysis and verification, to ensure that each module can work stably in different environments; then the system function and specification parameters for simulation; finally completed layout design. The simulation results show that the input voltage range of 8~30V and when the input voltage is lower than 4.5V, the power switch off; dimming voltage range of 0.35~2.5V, when the dimming voltage is less than 0.3V, the power tube is closed; the input voltage changes in the range of 30V 8~, The output current variation is only 11mA, and the output current accuracy is as high as 97%. Under different dimming conditions, the dimming error is controlled within 3%. The chip has the advantages of high output current, high dimming, large output current and low cost.

【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM923.34

【参考文献】