- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Effects of repetitive polarization switching on the coercive voltage of Pt/Pb(Zr0.52Ti0.48)O3/Pt thin films analyzed using impedance spectroscopy
摘要： We investigated the effect of repetitive switching of polarization on the ferroelectric Pt/Pb(Zr0.52Ti0.48)O3/Pt thin film capacitor by using impedance spectroscopy. From the Cole-Cole plot, the equivalent circuit is described as a combination of the bulk part (a capacitor), the interface part (the constant phase element (CPE), and a parallelly-connected resistor). The circuit parameters were analyzed at various stages of switching. An early increase and a subsequent decrease of the bulk capacitance may represent the wake-up and fatigue phenomena, respectively. The change in the interface part was characterized by an increase in resistance and the growth of n, the exponent of CPE, which may have come from a reduction of defects and the diminished inhomogeneity in the interfacial layer, respectively. The change in the resistance and the coefficient of the CPE in the interface part collectively resulted in an increase in the interfacial impedance. The coercive voltage, which may have intrinsically increased due to the repetitive switching, was even larger as a result of the increased interfacial impedance.
关键词： Impedance spectroscopy,Wake-up,Coercive voltage,PZT,Fatigue
更新于2025-11-14 17:28:48
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A Wake-Up Receiver With a Multi-Stage Self-Mixer and With Enhanced Sensitivity When Using an Interferer as Local Oscillator
摘要： An ultra-low power wake-up receiver with an energy-detection passive-RF architecture uses a multi-stage self-mixer that has a better conversion gain than the conventional envelope detector. The self-mixer, co-designed with the RF matching network, optimizes the sensitivity and minimizes the power consumption of the receiver. A wake-up receiver prototype in 0.13-μm CMOS operates at 550 MHz, consumes 220 nW from 0.5 V, and achieves a sensitivity of ?56.4 dBm at a 400-kb/s chip rate using an 11-bit wake-up code. When a large interferer is present, the receiver operates in an interferer-enhanced mode, leveraging the interferer as a local oscillator to improve the sensitivity; in the presence of a ?43.5-dBm interferer, a ?63.6-dBm sensitivity is achieved while consuming 1.1 μW.
关键词： self-mixer,wake-up receivers (WuRXs),wake-up radios,low-power wide-area network (LPWAN),Envelope-detectors,low-power wireless
更新于2025-09-23 15:22:29
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[IEEE 2019 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD) - Ottawa, ON, Canada (2019.7.8-2019.7.12)] 2019 International Conference on Numerical Simulation of Optoelectronic Devices (NUSOD) - Modeling phase noise in high-power photodetectors
摘要： Enterprises can save a signi?cant energy by letting idle desktops sleep and awake them only when needed. Though existing mechanisms based on centralized or distributed sleep proxy scheme address this issue with good availability, which means that a sleeping machine can always be awoken when needed, they still feature some drawbacks, such as dedicated per-subnet servers, additional per-desktop CPU resource utilization, and extra energy consumption. This seriously impedes their widespread deployment in enterprises. We, thus, propose an improved scheme called wake-up system based on cloud (WaSCO). WaSCO not only provides high availability but also consumes low CPU resource and energy, as it does not need any speci?c server to help achieve high availability. This system of?oads heavy computation from desktops to a stable cloud, which is responsible for managing agents in various subnets by using our proposed algorithm called choosing-and-guaranteeing (CGA) algorithm. When a remote user wakes up a desktop with WaSCO, the cloud sends a message to the selected agents in the subnet, which then send wake-on-LAN packets to wake up the target desktop. In essence, CGA algorithm ensures running agents in each subnet, dynamically adjusts the number of agents, and selects a few desktops, rather than all the desktops, as agents. Experimental results show that WaSCO outperforms centralized and distributed sleep proxy mechanisms in terms of deployment cost, CPU resource cost, and energy consumption, while still maintains high availability.
关键词： Wake-up,energy,cloud,CPU,availability
更新于2025-09-19 17:13:59
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Fast UV-Curing Encapsulation for GaN-Based Light-Emitting Diodes
摘要： Enterprises can save a signi?cant energy by letting idle desktops sleep and awake them only when needed. Though existing mechanisms based on centralized or distributed sleep proxy scheme address this issue with good availability, which means that a sleeping machine can always be awoken when needed, they still feature some drawbacks, such as dedicated per-subnet servers, additional per-desktop CPU resource utilization, and extra energy consumption. This seriously impedes their widespread deployment in enterprises. We, thus, propose an improved scheme called wake-up system based on cloud (WaSCO). WaSCO not only provides high availability but also consumes low CPU resource and energy, as it does not need any speci?c server to help achieve high availability. This system of?oads heavy computation from desktops to a stable cloud, which is responsible for managing agents in various subnets by using our proposed algorithm called choosing-and-guaranteeing (CGA) algorithm. When a remote user wakes up a desktop with WaSCO, the cloud sends a message to the selected agents in the subnet, which then send wake-on-LAN packets to wake up the target desktop. In essence, CGA algorithm ensures running agents in each subnet, dynamically adjusts the number of agents, and selects a few desktops, rather than all the desktops, as agents. Experimental results show that WaSCO outperforms centralized and distributed sleep proxy mechanisms in terms of deployment cost, CPU resource cost, and energy consumption, while still maintains high availability.
关键词： CPU,energy,availability,Wake-up,cloud
更新于2025-09-19 17:13:59
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[IEEE 2019 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) - Auckland, New Zealand (2019.5.20-2019.5.23)] 2019 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) - Experimental characterization of off-the-shelf LEDs as photodetectors for waking up microcontrollers
摘要： The use of LEDs as photodetectors has been subject of study for a long time. However, LEDs manufacturers do not provide information about the response of LEDs to the light. It is essential for the designers of electronic devices to know what the behavior of LEDs is so as to develop new applications in this area. In this work, we propose the use of commercially off-the-shelf LEDs, illuminated by the flashlight of a smartphone, as a contactless wake-up system for microcontrollers that are in a sleep mode. In particular, the generated LED voltage is proposed as the wake-up signal. So, in order to choose the most suitable LED and depending of the main interfering light, the current- voltage (I-V) characterization of different kind of LEDs is performed for two scenarios: outdoors and indoors. It is demonstrated that placing a resistor in parallel with the LEDs allows a better discrimination between the LED voltage coming from the flashlight and that from the interfering lights. Results show that red and blue LEDs are more appropriate for outdoor and indoor applications, respectively.
关键词： wake-up system,LED,photodetector,microcontroller
更新于2025-09-11 14:15:04