用于AM-OLED的高性能DC-DC变换器设计  

Design of a High-performance DC-DC Converter Used for AM-OLED

作　　者：王琦[1] 魏廷存[1] 李博[1] 李勇[1] 夏佳佳[1] 

机构地区：[1]西北工业大学计算机学院,陕西西安710072

出　　处：《微电子学与计算机》2014年第4期103-107,共5页Microelectronics & Computer

基　　金：陕西省科技统筹创新工程计划项目(2011KTCQ01-22)

摘　　要：设计了一款用于AM-OLED驱动控制系统的高性能DC-DC变换器.该变换器可同时提供正压和负压输出.在误差放大器中通过引入负反馈,扩展了线性工作范围,减小了输出纹波,同时引入低压隔离电路,提高了系统启动速度.在比较器中采用轨对轨差动输入级,提高了系统动态响应速度,减小输出纹波.在PWM驱动电路中采用低功耗驱动电路,减小了系统功耗,提高了转换效率.采用0.16μm HV CMOS工艺对电路进行设计和Spice仿真,仿真结果表明,在工作频率为1.5MHz,输入电压在2.5~4.5V范围变化时,正向输出电压稳定在4.6V,负向输出电压可通过改变反馈电阻在-2.4^-6.4V范围内调节,输出纹波小于25mV,负载电流最高可达250mA,转换效率达85%以上,均满足AM-OLED驱动控制芯片的要求.This paper proposes the design of a high-performance DC-DC converter used for the AM-OLED driver and controller system. The converter can output both the positive and negative voltages at the same time. In the error amplifier, feedback resistor is used to enlarge the dynamic range and so as to reduce the output ripple, and the low voltage isolation circuit is also introduced to improve the system start speed. In the comparator, the rail-to-rail differential input stage is used to improve the dynamic response speed and so as to reduce the output ripple. In the PWM driver circuit, the low-power driving circuit is used to improve the conversion efficiency. The circuits are designed in 0. 16/~m HV CMOS process. The Spice simulation results show that, when the input voltage is changed from 2. 5V to 4. 5V and the operating frequency is 1.5 MHz, the positive output voltage is regulated to 4. 6V and the negative output voltage can be changed from-2. 4^--6.4V by adjusting the feedback resistors; furthermore the output ripples are less than 25 mV, the maximum load current can be 250mA, and the conversion efficiency is better than 85%, these performances are satisfied with the requirements of the AM-OLED driver and controller system.

关 键 词：AM-OLED DC-DC变换器 脉宽调制方式 误差放大器 负反馈 

分 类 号：TN402[电子电信—微电子学与固体电子学]