【作者】 黄东；

【导师】 唐路； 蒋颖丹；

【作者基本信息】 东南大学 ， 集成电路工程（专业学位）， 2021， 硕士

【摘要】 发光二极管(LED)是一种常用的新型高效固体光源,具有节能低功耗、绿色环保、使用寿命长等优点,符合市场应用和社会发展的需要。LED发光效率的不断提高,成本下降,LED显示屏作为发光二极管的一个重要应用,市场规模得以不断扩大,市场前景可观。LED显示屏在各行各业中的广泛应用,LED显示屏的恒流驱动芯片起到了重要作用。LED显示屏驱动芯片的不断优化,使得LED显示屏显示的图像视频更加清晰细腻、色彩更加自然真实。本设计基于LED显示屏驱动芯片的整体结构原理分析,根据具体的性能指标要求,重点对模拟电路部分主要子电路的基本原理进行深入分析,完成电路设计、进行仿真验证。本文设计的LED显示屏调光方式可以在模拟电路部分通过线性改变输出电流进行调光,内建的打散脉冲宽度调制(SPWM)调节方式可以提高刷新率和芯片的灰度调制能力,提高画面显示质量,SPWM是LED显示屏调光方式的一种重要调节方式,由数字模块产生用于控制输出通道电流,数字模块部分本文会重点介绍SPWM调节方式在LED显示屏灰度数据处理上的工作原理,对整体模拟电路加入SPWM调节方式进行模拟模块的仿真验证。最后介绍本设计芯片版图的布局布线中的设计要点,通过对流片后的芯片样片进行测试,测试结果表明各模块满足设计指标要求,芯片能较好实现功能。论文分析、设计并流片了一种16通道的LED显示屏恒流驱动芯片。使用0.18μm Bi CMOS工艺,电源电压范围3.3V～6V,各通道输出电流范围0.5m A～30m A,通道输出电流大小可调。本文设计恒流驱动芯片最高工作频率为35MHz,各通道之间输出电流最大误差不超过±1.5%,芯片间的输出电流误差低于±1.5%,本文设计芯片较高的输出电流精度有利于提高LED显示屏显示效果。更多还原

【Abstract】 Light Emitting Diode(LED)is a kind of new high efficient solid light source in common use.It has the advantages of energy saving,low power consumption,green environmental protection,long service life and so on.It meets the needs of market application and social development.With the continuous improvement of LED luminous efficiency and the decrease of cost,the LED display screen,as an important application of LED,continues to expand the market scale and has a promising market prospect.LED display is widely used in all walks of life,the constant current driver chip of LED display plays an important role.The continuous optimization of the LED display driver chip makes the images and videos displayed by the LED display more clear and delicate,and the colors more natural and real.This design is based on the analysis of the overall structure principle of the LED display driver chip.According to the specific performance requirements,it focuses on the in-depth analysis of the basic principles of the main sub-circuits of the analog circuit,and completes the circuit design and simulation verification.Ways in this paper,design of LED display dimming in analog circuit part through the linear change of output current dimmer,the built-in scattered adjusting mode pulse width modulation(SPWM)can increase the refresh rate and chip gray modulation ability,improve the quality of images showed.SPWM is a kind of important way of LED display light regulating mode,produced by the digital module is used to control the output channel current.The digital part of this paper will focus on SPWM control mode in the working principle of LED display gray data processing.The whole analog circuit is added with SPWM regulation mode to carry out simulation verification of the simulation module.Finally,the main points of the design of the layout and wiring of the chip layout are introduced.The test results show that each module meets the requirements of the design index and the chip can realize the function well.In this paper,a 16-channel LED display constant-current driver chip is analyzed,designed and streamed.Using 0.18μm BICMOS process,the power supply voltage range is 3.3V～6V,each channel output current range is 0.5m A～30m A,the channel output current size is adjustable.In this paper,the maximum operating frequency of the constant-current driver chip is 35 MHz,and the maximum error of the output current between channels is no more than ±1.5%,and the error of the output current between chips is less than ±1.5%.The high precision of the output current of the chip designed in this paper is conducive to improving the display effect of the LED display screen.更多还原