聚合物薄膜晶体管的制备及性能

以硅材料衬底作栅电极,在衬底上依次制备二氧化硅栅介质层、聚合物MEH-PPV薄膜半导体层和金源、漏电极,成功地得到了聚合物薄膜晶体管.器件的制备和测试都是在空气环境中完成.该薄膜晶体管呈现出较好的场效应晶体管饱和特性,器件的载流子迁移率为5.0×10-5 cm2/(V·s),开关电流比大于2×103.通过在氮气氛下对聚合物薄膜进行退火处理以及聚合物薄膜沉膜前对二氧化硅表面修饰可以适当地提高器件的载流子迁移率.     

A 1500 mA,10 MHz on-time controlled buck converter with ripple compensation and efficiency optimization

正A 1500 mA,10 MHz self-adaptive on-time(SOT) controlled buck DC-DC converter is presented.Both a low-cost ripple compensation scheme(RCS) and a self-adaptive on-time generator(SAOTG) are proposed to solve the system stability and frequency variation problem.Meanwhile a self-adaptive power transistor sizing(SAPTS) technique is used to optimize the efficiency especially with a heavy load.The circuit is implemented in a 2P4M 0.35μm CMOS process.A small external inductor of 0.47μH and a capacitor of 4.7μF are used to lower the cost of the converter and keep the output ripple to less than 10 mV.The measurement results show that the overshoot of the load transient response is 8 mV @ 200 mA step and the dynamic voltage scaling(DVS) performance is a rise of 16μs/V and a fall of 20μs/V.With a SAPTS technique and PFM control,the efficiency is maintained at more than 81%for a load range of 20 to 1500 mA and the peak efficiency reaches 88.43%.     

一种带双重纹波补偿的10MHZ导通时间纹波控制降压型转化器

A 10 MHz ripple-based on-time controlled buck converter is presented.A novel low-cost dual ripple compensation,which consists of coupling capacitor compensation and passive equivalent series resistance compensation, is proposed to achieve a fast load transient response and robust stability simultaneously.Implemented in a 2P4M 0.35μm CMOS process,the converter achieves fix-frequency output with a ripple of below 10 mV and an overshoot of 10 mV at 400 mA step load transient response.With width optimization of the power transistors in an ultra-heavy load and PFM control in a light load,the efficiency stays at over 83%for a load range from 20 mA to 1.5 A and the peak efficiency reaches 90.16%.     

一种带纹波补偿和效率优化的1500mA，10MHz导通时间控制降压型转化器

本文叙述了一种由自适应导通时间控制的1500mA,10MHz降压型转换器。文中提出的低成本纹波补偿技术和自适应导通时间产生电路分别解决了系统稳定性和频率变化问题。同时,一种自适应功率管分段技术被用于优化整体效率,特别是重负载下的效率。该转换器电路采用2P4M 0.35微米CMOS工艺流片验证。外部使用0.47μH电感和4.7μF电容以减小转换器成本,并保证输出纹波小于10mV。测试结果显示,负载跳变时的过冲为8mV每200mA,DVS性能为16μs/V上升和20μs/V下降。由于自适应功率管分段技术和PFM作用,转换器在20mA到1500mA范围内的整体效率保持在81%以上,同时峰值效率可达88.43%。