Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because th...Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.展开更多
Capacitive micromachined ultrasonic transducer(CMUT)technology is a potential candidate to implement an ultrasonic power receiver for implantable medical devices(IMDs)because CMUT technology employs photolithography-b...Capacitive micromachined ultrasonic transducer(CMUT)technology is a potential candidate to implement an ultrasonic power receiver for implantable medical devices(IMDs)because CMUT technology employs photolithography-based microfabrication techniques amenable to miniaturization,integration with electronics,and biocompatibility.Pre-charged CMUTs operating in constant-charge mode eliminate the DC bias and this mode of operation is more suitable for ultrasound power transfer to IMDs.We designed and fabricated a novel pre-charged CMUT structure with a built-in charge storage capacitor.This new configuration features a floating electrode between the upper and lower electrodes.Charges are stored on this floating electrode prior to implantation by directly bringing the floating electrode into contact with the bottom electrode while applying a DC bias between the top and bottom electrodes of the CMUT.After pre-charging the CMUT,the charges are retained without any leakage,as confirmed by occasional measurements over the course of about two years.We have also demonstrated that this device allows operation without a DC bias and can be used as a power receiver in an IMD.In the presented design,the CMUT can be pre-charged at a desired precise charge level.The amount of trapped charge can be controlled by holding the floating electrode in contact with the bottom electrode by applying external ultrasound pressure and simultaneously maintaining a DC bias.The maximum received power was 10.1 mW,corresponding to a received power density of 3.1 mW/mm2,with a 14.5%efficiency.We have achieved an acoustic-toelectrical power conversion efficiency as high as 29.7%at lower input power levels.展开更多
This paper describes the design and development of the timer based on liquid level measurement system in which timer 555 is used in astable mode. The capacitor charging time i. e. the ON time pulse width of the ti...This paper describes the design and development of the timer based on liquid level measurement system in which timer 555 is used in astable mode. The capacitor charging time i. e. the ON time pulse width of the timer output waveform which is measured using a digital storage oscillator （DSO）,is linearly proportional to the capacitance of a co-axial cylindrical capacitive transducer, and this capacitance once again linearly varies with the change in liquid level. Hence, we obtain a linear relationship between the liquid level and the capacitor charging time. The main advantages of this developed system are linear input-output relationship, small in size, easily portable, cost effective, and independent on the ambient temperature effect. The system can also be exploited to measure dielectric constant of liquid or solid in various process industries.展开更多
This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doubl...This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed charge-pump circuit is designed and simulated by SPICE with TSMC 0.35-μm CMOS technology and operates with a 2.7 to 3.6 V supply voltage. It has an area of 0.4 mm^2; it was designed with a frequency regulation of 1 MHz and internal current mode to reduce power consumption.展开更多
A novel high voltage switching circuit with parallel resonant topology is analyzed.Without adding other resonant components,this circuit makes full use of the transformer leakage inductance and winding capacitance so ...A novel high voltage switching circuit with parallel resonant topology is analyzed.Without adding other resonant components,this circuit makes full use of the transformer leakage inductance and winding capacitance so as to reduce the influence of the transformer parasitic parameter.Using device CD4046 to realize the switching control of MOS,this circuit can realize the constant-current charging to capacitor by operating the above resonance.The operating process of the circuit is analyzed,and the power calculation and some practical waveforms are given.展开更多
Recently, triboelectric generator(TEG) has attracted a lot of attention due to its high output voltage and low-cost fabrication process. Here, a novel cubic TEG box is designed, which has separated electrodes on diffe...Recently, triboelectric generator(TEG) has attracted a lot of attention due to its high output voltage and low-cost fabrication process. Here, a novel cubic TEG box is designed, which has separated electrodes on different surfaces. Thanks to the specially designed structure, it can scavenge vibration energy from all directions. Firstly the device is investigated through finite element method(FEM) simulation. Then the device is evaluated by experiments. The measuremental results show that this device can generate an amount of 25 n C charge during once shake by charging a 10 n F capacitor. Besides, an output voltage about 100 V is obtained, which is able to directly light up several light-emitting diodes(LEDs) simultaneously. At last, the device is utilized as a self-powered orientation sensor, which shows explicit directivity. This work extends the applications of TEG for ambient vibration energy harvesting techniques and the self-powered orientation sensor.展开更多
文摘Correction to:Nano-Micro Letters(2025)17:117 https://doi.org/10.1007/s40820-025-01660-0 Following publication of the original article[1],the authors reported that the supplementary file needed to be updated because they mistakenly used the incorrect version.The original article[1]has been corrected.
基金supported by the NSF under Grant 1160483 as part of a Centreto-Center collaborative partnership with NUI Galway,Ireland and Queen’s University,Belfast,Northern Irelandperformed in part at the NCSU Nanofabrication Facility(NNF),and Duke University Shared Materials Instrumentation Facility(SMIF),all of which are members of the North Carolina Research Triangle Nanotechnology Network(RTNN)which is supported by the National Science Foundation(Grant ECCS-2025064)as part of the National Nanotechnology Coordinated Infrastructure(NNCI).
文摘Capacitive micromachined ultrasonic transducer(CMUT)technology is a potential candidate to implement an ultrasonic power receiver for implantable medical devices(IMDs)because CMUT technology employs photolithography-based microfabrication techniques amenable to miniaturization,integration with electronics,and biocompatibility.Pre-charged CMUTs operating in constant-charge mode eliminate the DC bias and this mode of operation is more suitable for ultrasound power transfer to IMDs.We designed and fabricated a novel pre-charged CMUT structure with a built-in charge storage capacitor.This new configuration features a floating electrode between the upper and lower electrodes.Charges are stored on this floating electrode prior to implantation by directly bringing the floating electrode into contact with the bottom electrode while applying a DC bias between the top and bottom electrodes of the CMUT.After pre-charging the CMUT,the charges are retained without any leakage,as confirmed by occasional measurements over the course of about two years.We have also demonstrated that this device allows operation without a DC bias and can be used as a power receiver in an IMD.In the presented design,the CMUT can be pre-charged at a desired precise charge level.The amount of trapped charge can be controlled by holding the floating electrode in contact with the bottom electrode by applying external ultrasound pressure and simultaneously maintaining a DC bias.The maximum received power was 10.1 mW,corresponding to a received power density of 3.1 mW/mm2,with a 14.5%efficiency.We have achieved an acoustic-toelectrical power conversion efficiency as high as 29.7%at lower input power levels.
文摘This paper describes the design and development of the timer based on liquid level measurement system in which timer 555 is used in astable mode. The capacitor charging time i. e. the ON time pulse width of the timer output waveform which is measured using a digital storage oscillator （DSO）,is linearly proportional to the capacitance of a co-axial cylindrical capacitive transducer, and this capacitance once again linearly varies with the change in liquid level. Hence, we obtain a linear relationship between the liquid level and the capacitor charging time. The main advantages of this developed system are linear input-output relationship, small in size, easily portable, cost effective, and independent on the ambient temperature effect. The system can also be exploited to measure dielectric constant of liquid or solid in various process industries.
文摘This paper presents a novel organization of switch capacitor charge pump circuits based on voltage doubler structures. Each voltage doubler takes a DC input and outputs a doubled DC voltage. By cascading voltage doublers the output voltage increases up to 2 times. A two-phase voltage doubler and a multiphase voltage doubler structures are discussed and design considerations are presented. A simulator working in the Q-V realm was used for simplified circuit level simulation. In order to evaluate the power delivered by a charge pump, a resistive load is attached to the output of the charge pump and an equivalent capacitance is evaluated. To avoid the short circuit during switching, a clock pair generator is used to achieve multi-phase non-overlapping clock pairs. This paper also identifies optimum loading conditions for different configurations of the charge pumps. The proposed charge-pump circuit is designed and simulated by SPICE with TSMC 0.35-μm CMOS technology and operates with a 2.7 to 3.6 V supply voltage. It has an area of 0.4 mm^2; it was designed with a frequency regulation of 1 MHz and internal current mode to reduce power consumption.
文摘A novel high voltage switching circuit with parallel resonant topology is analyzed.Without adding other resonant components,this circuit makes full use of the transformer leakage inductance and winding capacitance so as to reduce the influence of the transformer parasitic parameter.Using device CD4046 to realize the switching control of MOS,this circuit can realize the constant-current charging to capacitor by operating the above resonance.The operating process of the circuit is analyzed,and the power calculation and some practical waveforms are given.
基金supported by the National Natural Science Foundation of China(Grant Nos.61176103,91323304)the National High-Tech Research and Development Program of China("863"Project)(Grant No.2013AA041102)the Beijing Natural Science Foundation of China(Grant No.4141002)
文摘Recently, triboelectric generator(TEG) has attracted a lot of attention due to its high output voltage and low-cost fabrication process. Here, a novel cubic TEG box is designed, which has separated electrodes on different surfaces. Thanks to the specially designed structure, it can scavenge vibration energy from all directions. Firstly the device is investigated through finite element method(FEM) simulation. Then the device is evaluated by experiments. The measuremental results show that this device can generate an amount of 25 n C charge during once shake by charging a 10 n F capacitor. Besides, an output voltage about 100 V is obtained, which is able to directly light up several light-emitting diodes(LEDs) simultaneously. At last, the device is utilized as a self-powered orientation sensor, which shows explicit directivity. This work extends the applications of TEG for ambient vibration energy harvesting techniques and the self-powered orientation sensor.
