When using traditional drive circuits,the enhancement-mode GaN(eGaN)HEMT will be affected by high switching speed characteristics and parasitic parameters leading to worse crosstalk problems.Currently,the existing cro...When using traditional drive circuits,the enhancement-mode GaN(eGaN)HEMT will be affected by high switching speed characteristics and parasitic parameters leading to worse crosstalk problems.Currently,the existing crosstalk suppression drive circuits often have the disadvantages of increased switching loss,control complexity,and overall electromagnetic interference(EMI).Therefore,this paper combines the driving loop impedance control and the active Miller clamp method to propose an improved active Miller clamp drive circuit.First,the crosstalk mechanism is analyzed,and the crosstalk voltage model is established.Through the crosstalk voltage evaluation platform,the influencing factors are evaluated experimentally.Then,the operating principle of the improved active Miller clamp drive circuit is discussed,and the optimized parameter design method is given.Finally,the effect of the improved active Miller clamp method for suppressing crosstalk is experimentally verified.The crosstalk voltage was suppressed from 3.5 V and-3.5 V to 1 V and-1.3 V,respectively,by the improved circuit.展开更多
The severe crosstalk effect is widely present in tactile sensor arrays with a sandwich structure.Here we present a novel design for a resistive tactile sensor array with a coplanar electrode layer and isolated sensing...The severe crosstalk effect is widely present in tactile sensor arrays with a sandwich structure.Here we present a novel design for a resistive tactile sensor array with a coplanar electrode layer and isolated sensing elements,which were made from polydimethylsiloxane(PDMS)doped with multiwalled carbon nanotubes(MWCNTs)for crosstalk suppression.To optimize its properties,both mechanical and electrical properties of PDMS/MWCNT-sensing materials with different PDMS/MWCNT ratios were investigated.The experimental results demonstrate that a 4 wt% of MWCNTs to PDMS is optimal for the sensing materials.In addition,the pressure-sensitive layer consists of three microstructured layers(two aspectant PDMS/MWCNT-based films and one top PDMS-based film)that are bonded together.Because of this three-layer microstructure design,our proposed tactile sensor array shows sensitivity up to−1.10 kPa^(−1),a response time of 29 ms and reliability in detecting tiny pressures.展开更多
Although tremendous efforts have been devoted to investigating planar single-conductor circuits,it remains challenging to provide tight confinement of electromagnetic field and compatibility with active semi-conductor...Although tremendous efforts have been devoted to investigating planar single-conductor circuits,it remains challenging to provide tight confinement of electromagnetic field and compatibility with active semi-conductor components such as amplifier,harmonic generator and mixers.Single-conductor spoof surface plasmon polariton(SSPP)structure,which is one of the most promising planar single-conductor transmission media due to the outstanding field confinement,still suf-fers from the difficulty in integrating with the active semi-conductor components.In this paper,a new kind of odd-mode-metachannel(OMM)that can support odd-mode SSPPs is proposed to perform as the fundamental transmission chan-nel of the single-conductor systems.By introducing zigzag decoration,the OMM can strengthen the field confinement and broaden the bandwidth of odd-mode SSPPs simultaneously.More importantly,the active semi-conductor amplifier chip integration is achieved by utilizing the intrinsic potential difference on OMM,which breaks the major obstacle in im-plementing the single-conductor systems.As an instance,an amplifier is successfully integrated on the single-conductor OMM,which can realize both loss compensation and signal amplification.Meanwhile,the merits of OMM including crosstalk suppression,low radar cross section(RCS),and flexibility are comprehensively demonstrated.Hence,the pro-posed OMM and its capability to integrate with the active semi-conductor components may provide a new avenue to fu-ture single-conductor conformal systems and smart skins.展开更多
With the requirements of self-powering sensors in flexible electronics,wearable triboelectric nanogenerators(TENGs)have attracted great attention due to their advantages of excellent electrical outputs and low-cost pr...With the requirements of self-powering sensors in flexible electronics,wearable triboelectric nanogenerators(TENGs)have attracted great attention due to their advantages of excellent electrical outputs and low-cost processing routes.The crosstalk effect between adjacent sensing units in TENGs significantly limits the pixel density of sensor arrays.Here,we present a skin-integrated,flexible TENG sensor array with 100 sensing units in an overall size of 7.5 cm×7.5 cm that can be processed in a simple,low-cost,and scalable way enabled by 3D printing.All the sensing units show good sensitivity of 0.11 V/kPa with a wide range of pressure detection from 10 to 65 kPa,which allows to accurately distinguish various tactile formats from gentle touching(as low as 2 kPa)to hard pressuring.The 3D printing patterned substrate allows to cast triboelectric layers of polydimethylsiloxane in an independent sensing manner for each unit,which greatly suppresses the cross talk arising from adjacent sensing units,where the maximum crosstalk output is only 10.8%.The excellent uniformity and reproducibility of the sensor array offer precise pressure mapping for complicated pattern loadings,which demonstrates its potential in tactile sensing and human-machine interfaces.展开更多
基金supported by the Foundation of State Key Laboratory of Wide-Bandgap Semi-conductor Power Electronic Devices(No.2019KF001)National Natural Science Foundation of China(No.51677089)。
文摘When using traditional drive circuits,the enhancement-mode GaN(eGaN)HEMT will be affected by high switching speed characteristics and parasitic parameters leading to worse crosstalk problems.Currently,the existing crosstalk suppression drive circuits often have the disadvantages of increased switching loss,control complexity,and overall electromagnetic interference(EMI).Therefore,this paper combines the driving loop impedance control and the active Miller clamp method to propose an improved active Miller clamp drive circuit.First,the crosstalk mechanism is analyzed,and the crosstalk voltage model is established.Through the crosstalk voltage evaluation platform,the influencing factors are evaluated experimentally.Then,the operating principle of the improved active Miller clamp drive circuit is discussed,and the optimized parameter design method is given.Finally,the effect of the improved active Miller clamp method for suppressing crosstalk is experimentally verified.The crosstalk voltage was suppressed from 3.5 V and-3.5 V to 1 V and-1.3 V,respectively,by the improved circuit.
基金We are thankful for the partial financial support from the National Natural Science Foundation of China(no.51475307)the 973 Program(2013CB329401)SRFDP(20130073110087).
文摘The severe crosstalk effect is widely present in tactile sensor arrays with a sandwich structure.Here we present a novel design for a resistive tactile sensor array with a coplanar electrode layer and isolated sensing elements,which were made from polydimethylsiloxane(PDMS)doped with multiwalled carbon nanotubes(MWCNTs)for crosstalk suppression.To optimize its properties,both mechanical and electrical properties of PDMS/MWCNT-sensing materials with different PDMS/MWCNT ratios were investigated.The experimental results demonstrate that a 4 wt% of MWCNTs to PDMS is optimal for the sensing materials.In addition,the pressure-sensitive layer consists of three microstructured layers(two aspectant PDMS/MWCNT-based films and one top PDMS-based film)that are bonded together.Because of this three-layer microstructure design,our proposed tactile sensor array shows sensitivity up to−1.10 kPa^(−1),a response time of 29 ms and reliability in detecting tiny pressures.
基金financial supports from the National Natural Science Foundation of China under Grant Nos.62101122,61871127,61701108 and 61631007Natural Science Foundation of Jiangsu Province under Grant BK20210212the 111 Project under Grant No.111-2-05.
文摘Although tremendous efforts have been devoted to investigating planar single-conductor circuits,it remains challenging to provide tight confinement of electromagnetic field and compatibility with active semi-conductor components such as amplifier,harmonic generator and mixers.Single-conductor spoof surface plasmon polariton(SSPP)structure,which is one of the most promising planar single-conductor transmission media due to the outstanding field confinement,still suf-fers from the difficulty in integrating with the active semi-conductor components.In this paper,a new kind of odd-mode-metachannel(OMM)that can support odd-mode SSPPs is proposed to perform as the fundamental transmission chan-nel of the single-conductor systems.By introducing zigzag decoration,the OMM can strengthen the field confinement and broaden the bandwidth of odd-mode SSPPs simultaneously.More importantly,the active semi-conductor amplifier chip integration is achieved by utilizing the intrinsic potential difference on OMM,which breaks the major obstacle in im-plementing the single-conductor systems.As an instance,an amplifier is successfully integrated on the single-conductor OMM,which can realize both loss compensation and signal amplification.Meanwhile,the merits of OMM including crosstalk suppression,low radar cross section(RCS),and flexibility are comprehensively demonstrated.Hence,the pro-posed OMM and its capability to integrate with the active semi-conductor components may provide a new avenue to fu-ture single-conductor conformal systems and smart skins.
基金This work was supported in part by InnoHK Project on Project 2.2-AI-based 3D ultrasound imaging algorithm at Hong Kong Centre for Cerebro-cardiovascular Health Engineering(COCHE),in part by Research Grants Council of the Hong Kong Special Administrative Region(21210820,and 11213721)in part by Shenzhen Science and Technology Innovation Commission(JCYJ20200109110201713)in part by National Natural Science Foundation of China(62122002,and U21A20492).
文摘With the requirements of self-powering sensors in flexible electronics,wearable triboelectric nanogenerators(TENGs)have attracted great attention due to their advantages of excellent electrical outputs and low-cost processing routes.The crosstalk effect between adjacent sensing units in TENGs significantly limits the pixel density of sensor arrays.Here,we present a skin-integrated,flexible TENG sensor array with 100 sensing units in an overall size of 7.5 cm×7.5 cm that can be processed in a simple,low-cost,and scalable way enabled by 3D printing.All the sensing units show good sensitivity of 0.11 V/kPa with a wide range of pressure detection from 10 to 65 kPa,which allows to accurately distinguish various tactile formats from gentle touching(as low as 2 kPa)to hard pressuring.The 3D printing patterned substrate allows to cast triboelectric layers of polydimethylsiloxane in an independent sensing manner for each unit,which greatly suppresses the cross talk arising from adjacent sensing units,where the maximum crosstalk output is only 10.8%.The excellent uniformity and reproducibility of the sensor array offer precise pressure mapping for complicated pattern loadings,which demonstrates its potential in tactile sensing and human-machine interfaces.