设计了一个基于金属氧化物薄膜晶体管工艺的8位电流舵数/模转换器(Digital to Analog Converter,DAC),包括定时刷新模块、同步寄存器电路、分段译码电路、开关驱动电路、开关阵列和电流源阵列、多路选择器网络、随机序列发生器。在数字...设计了一个基于金属氧化物薄膜晶体管工艺的8位电流舵数/模转换器(Digital to Analog Converter,DAC),包括定时刷新模块、同步寄存器电路、分段译码电路、开关驱动电路、开关阵列和电流源阵列、多路选择器网络、随机序列发生器。在数字电路中设计定时刷新结构解决了传统的自举逻辑门电荷泄露导致的电流源开关驱动电压的下降,避免了在低频信号下采样出错问题的发生。提出采用差分对偶译码的结构,保证打开和关闭两路信号可以同时到达开关驱动电路,保证驱动电路中电压上升和下降窗口的对称性,减小输出的毛刺;同时利用数字电路中的D触发器和译码电路中的逻辑门实现驱动增强电路,保证可以驱动模拟电路中的高位单位电流源,提高转换速率;利用动态元件匹配(Dynamic Elements Matching,DEM)技术提高DAC的动态性能。后仿真结果表明,所设计的DAC面积为73 mm 2,功耗为6.5 mW,输出电流摆幅为301.46μA,最大转换速率为32 kS/s,在单位电流源的随机匹配误差的标准差为0.1的条件下,奈奎斯特频率下的无杂散动态范围(Spurious-Free Dynamic Range,SFDR)可达到42.43 dB,最大的微分非线性(Differential Nonlinearity,DNL)为0.36 LSB,最大的积分非线性(Integral Nonlinearity,INL)为1.75 LSB,满足生物医学用柔性电子系统的需求。展开更多
电极片品质对液晶屏幕的显示效果极为关键。针对薄膜晶体管(Thin Film Transistor,TFT)电极板中缺陷尺寸微小、缺陷类别繁多、背景干扰因素多等问题,设计了一项基于改进的YOLOv5全新的视觉算法模型,可以实现对TFT电极板上常见缺陷的精...电极片品质对液晶屏幕的显示效果极为关键。针对薄膜晶体管(Thin Film Transistor,TFT)电极板中缺陷尺寸微小、缺陷类别繁多、背景干扰因素多等问题,设计了一项基于改进的YOLOv5全新的视觉算法模型,可以实现对TFT电极板上常见缺陷的精准识别。改进的视觉算法模型通过将卷积块注意力模块(Con-volutional Block Attention Module,CBAM)机制融合到YOLOv5的核心网络架构中,有效降低了缺陷背景干扰的影响,并显著提升了对缺陷特征点的检测识别效果。在TFT电极板常见缺陷数据集上进行测试,测试结果显示,修改后的新算法对TFT电极板异物、划痕、裂片和油污4类缺陷的平均检测精度均有提升。展开更多
The development of artificial photosensitive synapses with high sensitivity and biomimetic properties that combine innovative concepts and neuromorphic architectures is crucial to achieving highly integrated and flexi...The development of artificial photosensitive synapses with high sensitivity and biomimetic properties that combine innovative concepts and neuromorphic architectures is crucial to achieving highly integrated and flexible intelligent visual systems.Recently,graphene heterostructure-based photosensitive synaptic transistors have been extensively studied for this purpose.However,compared to traditional transistors,vertical structure thin film transistors(VTFTs)with ultra-short channels and advantages,such as high integration,have yet to be investigated in photosensitive synapses.Here,we report an ultra-thin VTFT featuring a graphene/W_(x)Se_(x-1)van der Waals heterostructure that combines photonic and neuromorphic elements.We demonstrate a VTFT in which the channel layer is formed by covalently bonded W_(x)Se_(x-1)nanomaterials produced by introducing Se atoms on the surface of a tungsten metal thin film deposited via radio-frequency sputtering.This structure successfully simulated the main synaptic function,exhib-ited photosensitive synaptic responses to ultraviolet(λ=365 nm)light,and demonstrated highly reliable electrical performance.Furthermore,the incorporation of gold nanoparticles changed the photosensitive synaptic response properties of the graphene/W_(x)Se_(x-1)heterostructure from excitatory to inhibitory,show-ing a responsivity of about∼14 A W-1,which was attributed to the heterojunction interface resonant effects and efficient charge transfer induced by localized surface plasmons.This further enabled optical artificial synaptic applications while operating with low voltage spikes and low light intensity.This work provides a novel strategy for integrating and developing biological and nano-electronic systems.展开更多
文摘设计了一个基于金属氧化物薄膜晶体管工艺的8位电流舵数/模转换器(Digital to Analog Converter,DAC),包括定时刷新模块、同步寄存器电路、分段译码电路、开关驱动电路、开关阵列和电流源阵列、多路选择器网络、随机序列发生器。在数字电路中设计定时刷新结构解决了传统的自举逻辑门电荷泄露导致的电流源开关驱动电压的下降,避免了在低频信号下采样出错问题的发生。提出采用差分对偶译码的结构,保证打开和关闭两路信号可以同时到达开关驱动电路,保证驱动电路中电压上升和下降窗口的对称性,减小输出的毛刺;同时利用数字电路中的D触发器和译码电路中的逻辑门实现驱动增强电路,保证可以驱动模拟电路中的高位单位电流源,提高转换速率;利用动态元件匹配(Dynamic Elements Matching,DEM)技术提高DAC的动态性能。后仿真结果表明,所设计的DAC面积为73 mm 2,功耗为6.5 mW,输出电流摆幅为301.46μA,最大转换速率为32 kS/s,在单位电流源的随机匹配误差的标准差为0.1的条件下,奈奎斯特频率下的无杂散动态范围(Spurious-Free Dynamic Range,SFDR)可达到42.43 dB,最大的微分非线性(Differential Nonlinearity,DNL)为0.36 LSB,最大的积分非线性(Integral Nonlinearity,INL)为1.75 LSB,满足生物医学用柔性电子系统的需求。
基金supported by the National Research Foundation of Korea,funded by the Korean government(Nos.2016R1A3B1908249 and 2020R1A2C3013480).
文摘The development of artificial photosensitive synapses with high sensitivity and biomimetic properties that combine innovative concepts and neuromorphic architectures is crucial to achieving highly integrated and flexible intelligent visual systems.Recently,graphene heterostructure-based photosensitive synaptic transistors have been extensively studied for this purpose.However,compared to traditional transistors,vertical structure thin film transistors(VTFTs)with ultra-short channels and advantages,such as high integration,have yet to be investigated in photosensitive synapses.Here,we report an ultra-thin VTFT featuring a graphene/W_(x)Se_(x-1)van der Waals heterostructure that combines photonic and neuromorphic elements.We demonstrate a VTFT in which the channel layer is formed by covalently bonded W_(x)Se_(x-1)nanomaterials produced by introducing Se atoms on the surface of a tungsten metal thin film deposited via radio-frequency sputtering.This structure successfully simulated the main synaptic function,exhib-ited photosensitive synaptic responses to ultraviolet(λ=365 nm)light,and demonstrated highly reliable electrical performance.Furthermore,the incorporation of gold nanoparticles changed the photosensitive synaptic response properties of the graphene/W_(x)Se_(x-1)heterostructure from excitatory to inhibitory,show-ing a responsivity of about∼14 A W-1,which was attributed to the heterojunction interface resonant effects and efficient charge transfer induced by localized surface plasmons.This further enabled optical artificial synaptic applications while operating with low voltage spikes and low light intensity.This work provides a novel strategy for integrating and developing biological and nano-electronic systems.
