Novel Polymeric Metal Complexes for Dye Sensitizer: Synthesis and Photovoltaic Performances

Four novel polymeric metal complexes with a D–A–π–A motif, BDTT-PY-Cd, BDTT-PY-Zn, BDTT-PY-Cu and BDTT-PY-Ni, were designed, synthesized and characterized. These polymeric metal complexes were made up with Cd(II), Zn(II), Cu(II), Ni(II) complexes, thienylbenzo-[1,2-b:4,5-b'] dithiophene (BDTT) and the 8-quinolinol derivative, which were used severally as dye sensitzers’ auxiliary electron acceptors (A), electron donor (D) and π bridges as well as the acceptors (A). Under AM 1.5 irradiation (100 mW cm^?2), the devices of dye sensitized solar cells (DSSC) based on four polymer complexes exhibited short-circuit photocurrent densities (J_sc) of 17.45 mA cm^?2, 14.75 mA cm^?2, 13.94 mA cm^?2 and 12.00 mA cm^?2, as well as attractive power conversion efficiencies (PCE) of were 9.73%, 8.02%, 6.82% and 6.12%, respectively. The photovoltaic conversion efficiency (PCE) and short-circuit photocurrent density (J_sc) of BDTT-PY-Cd, BDTT-PY-Zn, BDTT-PY-Cu and BDTT-PY-Ni decrease in order because the radius and charge number of the metal ion affect the strength of the coordination bond between the metal ion and the ligand. These results provides a new way of development for efficient and stable dye sensitizers in the future.

     

用于相变存储器的超低输出纹波2X/1.5X电荷泵

本文针对相变存储器编程驱动电路,提出了一种超低输出电压纹波的开关电容型电荷泵。该电荷泵可根据输入电压的不同,自适应工作在2X/1.5X升压模式之间,以获得更高的电源转换效率。相比于传统开关电容型电荷泵,在充电阶段泵电容被充电至预先设定的电压值Vo-VDD(Vo为预期的输出电压);放电阶段,泵电容串联在输入电压VDD与输出端,通过此方法将电荷泵输出端电压稳定在Vo,并有效的降低了由于电荷分享所造成的输出纹波。在中芯国际40nm标准CMOS工艺模型下,对电路进行了仿真验证,结果表明在输入电压为1.6-2.1V,输出2.5V电压,最大负载电流为10mA,输出电压纹波低于4mV,电源效率最高可达91%。     

Variables Bounding Based Retiming Algorithm

Retiming is a technique for optimizing sequential circuits.In this paper,we discuss this problem and propose an improved retiming algorithm based on varialbes bounding.Through the computation of the lower and upper bounds on variables,the algorithm can significantly reduce the number of constratints and speed up the execution of retiming.Furthermore,the elements of matrixes D and W are computed in a demand-driven way,which can reduce the capacity of memory,It is shown through the experimental results on ISCAS89 benchmarks that our algorithm is very effective for large-scale seuqential circuits.     

一种基于电流阶梯波的相变存储器擦驱动电路

基于相变存储器的擦操作(SET)特性,设计了一种能够产生电流阶梯波的相变存储器擦驱动电路,采用130 nm标准CMOS工艺将其与128 kb的相变存储器实验芯片集成.相比传统的单一电流脉冲擦驱动电路,这种改进后的擦驱动电路能将相变存储单元的电阻均值从15 kΩ左右降至7 kΩ左右,并且存储阵列的阻值分布一致性也得到提升...     

一种1kb相变存储芯片的设计

以中科院上海微系统与信息技术研究所自主研发的相变存储器工艺为基础,开发了一款容量为1 kb、可应用于射频标签(RFID)的嵌入式相变存储芯片.该芯片以1T1R为基本单元结构,采用箝位读出方式以及电流镜式写驱动电路,成功实现了相变存储器的读写功能.测试结果显示,该芯片可重复擦写次数达到107次,在80℃条件下数据保持力达...     

Dynamics simulation of bottom high-sediment sea water movement under waves

The movement of bottom high-sediment sea water under water waves, especially that of the high-sediment water layer close to the sea bottom, is important to the resuspension and settlement of sediment. Supposing that the high-sediment sea water is a Newtonian fluid, based on Navier-Stokes (N-S) theory, the movement of the interfaces of air-water and water-sediment water was tracked by the volume of fluid (VOF) method. The velocity field of sediment water was simulated by considering the effect of water waves. The results show that the movement of sediment water is very different from that of sea water, which provides a solid basis for understanding the resuspension and settlement of sediment and the formation of bottom stripe, and the VOF method can trace the movement of the two interfaces simultaneously; the movement of the air-water interface has a strong effect on that of the water-sediment water interface, while the effect of the water-sediment water interface movement on the air-water interface is not obvious. __________ Translated from Journal of Tianjin University, 2008, 41(2): 285-290 [译自: 天津大学学报]     

一种相变存储器读出电路及其快速读出方法

针对大规模相变存储器所具有的寄生电容大、可能出现读破坏现象等特性,提出了一种读电压模式的相变存储器读出电路及其快速读出方法。基于SMIC 40nm CMOS工艺的仿真结果表明,在2.5V电源电压下,该方法可以在90ns的读出周期内正确读出位线寄生电容为30pF的存储单元数据,同时,该读出周期随位线寄生电容的减小而减小。另外,该方法可以和传统的Burst等快速读出方式并存,非常适用于带数据预读机制的高端存储器技术。     

基于PCRAM的射频标签模拟前端关键电路设计

基于相变存储器,对无源超高频电子标签模拟前端四个关键电路进行低功耗设计。整流电路采用9级电荷泵,结合储能电容和过压保护电路,得到了很好的整流效果。上电复位电路在箝位电路的基础上利用简单的缓冲器及异或逻辑,得到性能良好的矩形脉冲复位信号PORB,通过PMOS栅交叉耦合,极大地降低了电路静态电流(<1nA)。在基准电源电路中,设计了双极晶体管和MOS晶体管,兼具功耗低和准确性高的优势。稳压电路采用串联稳压结构,电源抑制比达到28.2dB。仿真结果显示,功耗达到nA级,输出直流电压为3V。     

基于0.13μm工艺的8Mb相变存储器

采用0.13 μm工艺,4层金属布线,在标准CMOS技术的基础上增加3张掩膜制备了一款8 Mb相变存储器.1.2V的低压NMOS管作为单元选通器,单元大小为50 F2.外围电路采用3.3V工作电压的CMOS电路.Set和Reset操作电流分别为0.4 mA和2 mA.读出操作的电流为10 μA,芯片疲劳特性次数超过了1...     

一种瞬态增强的无片外电容LDO设计

针对无片外电容型低压差线性稳压器(LDO)瞬态响应差的问题,基于40 nm CMOS工艺设计了一种带瞬态负载变化感知的无片外电容型LDO电路。采用有源前馈频率补偿,实现了电路稳定;瞬变检测电路感应负载的变化,为功率管栅极提供充、放电通路,减弱了输出电压波动。仿真结果表明,负载电流在0~100 mA范围内,该LDO的输出过冲电压和下冲电压分别为100 mV和140 mV,稳定时间在1 μs以内。全负载电流范围内,瞬态性能大幅提升。