虫虫首页| 资源下载| 资源专辑| 精品软件
登录| 注册

Limit

  • Baseband+Receiver+Algorithms

    The growing interest for high data rate wireless communications over the last few decades gave rise to the emergence of a number of wideband wireless systems. The resulting scarcity of frequency spectrum has been forcing wireless system designers to develop methods that will push the spectral efficiency to its Limit.

    标签: Algorithms Baseband Receiver

    上传时间: 2020-05-26

    上传用户:shancjb

  • Opportunistic+Spectrum+Sharing

    Rapid growth of wireless communication services in recent decades has created a huge demand of radio spectrum. Spectrum scarcity and utilization inefficiency Limit the development of wireless networks. Cognitive radio is a promising tech- nology that allows secondary users to reuse the underutilized licensed spectrum of primary users. The major challenge for spectrum sharing is to achieve high spectrum efficiency while making non-intrusive access to the licensed bands. This requires in- formation of availability and quality of channel resources at secondary transmitters, however, is difficult to be obtained perfectly in practice.

    标签: Opportunistic Spectrum Sharing

    上传时间: 2020-05-31

    上传用户:shancjb

  • Radio Wave Propagation

    One of the prerequisites for the development of telecommunication services is the understanding of the propagation of the waves, either acoustic, electromagnetic, radio or light waves, which are used for the transmission of information. In this work, we shall Limit ourselves to the study of radio waves: this term apply to the electromagnetic waves used in radio communications. Their frequency spectrum is very broad, and is divided into the following frequency bands : ELF waves (f < 3 kHz), VLF (3-30 kHz), LF waves (30-300 kHz), MF waves (300-3000 kHz), HF (3-30 MHz), VHF waves (30-300 MHz), UHF waves (300-3000 MHz), SHF waves (3-30 GHz), EHF waves (30-300 GHz) and sub- EHF waves (300-3000 GHz).

    标签: Propagation Radio Wave

    上传时间: 2020-06-01

    上传用户:shancjb

  • CMOS MEMS_ A KEY TECHNOLOGY

    The mature CMOS fabrication processes are available in many IC foundries. It is cost-effective to leverage the existing CMOS fabrication technologies to implement MEMS devices. On the other hand, the MEMS devices could also add values to the IC industry as the Moore’s law reaching its Limit. The CMOS MEMS could play a key role to bridge the gap between the CMOS and MEMS technologies. The CMOS MEMS also offers the advantage of monolithic integration of ICs and micro mechanical components. 

    标签: TECHNOLOGY CMOS MEMS KEY

    上传时间: 2020-06-06

    上传用户:shancjb

  • POWERHVMOS_Devices_Compact_Modeling

    The continuous progress in modern power device technology is increasingly supported by power-specific modeling methodologies and dedicated simulation tools. These enable the detailed analysis of operational principles on the the device and on the system level; in particular, they allow the designer to perform trade- off studies by investigating the operation of competing design variants in a very early stage of the development process. Furthermore, using predictive computer simulation makes it possible to analyze the device and system behavior not only under regularoperatingconditions, but also at the rim of the safe-operatingarea and beyond of it, where destructive processes occur that Limit the lifetime of a power system.

    标签: POWERHVMOS_Devices_Compact_Modeli ng

    上传时间: 2020-06-07

    上传用户:shancjb

  • XR2981

    2.7V to 5.5V input voltage Range Efficiency up to 96%  24V Boost converter with 12A switch current Limit 600KHz fixed Switching Frequency Integrated soft-start Thermal Shutdown Under voltage Lockout Support external LDO auxiliary power supply 8-Pin SOP-PP PackageAPPLICATIONSPortable Audio Amplifier Power SupplyPower BankQC 2.0/Type CWireless ChargerPOS Printer Power SupplySmall Motor Power Supply

    标签: XR2981

    上传时间: 2021-11-05

    上传用户:

  • PW4055_2.0.pdf规格书下载

    The PW4055 is a complete constant-current /constant-voltage linear charger for single cell lithiumion batteries.Its ThinSOT package and low external component count make the PW4055 ideallysuited for portable applications.Furthermore, the PW4055 is specifically designed to work within USBpower specifications.The PW4055 No external sense resistor is needed, and no blocking diode is required due to theinternal MOSFET architecture.Thermal feedback regulates the charge current to Limit the dietemperature during high power operation or high ambient temperature. The charge voltage is fixedat 4.2V, and the charge current can be programmed externally with a single resistor. The PW4055automatically terminates the charge cycle when the charge current drops to 1/10th the programmedvalue after the final float voltage is reached. When the input supply (wall adapter or USB supply) isremoved, the PW4055 automatically enters a low current state, dropping the battery drain currentto less than 2µA. The PW4055 can be put into shutdown mode, reducing the supply current to 25µA.The BAT pin has a 7KV ESD(HBM) capability. Other features include charge current monitor, undervoltage lockout, automatic recharge and a status pin to indicate charge termination and the presenceof an input voltage

    标签: pw4055

    上传时间: 2022-02-11

    上传用户:jason_vip1

  • PW1555-2.0.pdf规格书

    PW1555 is a programmable current Limit switch with input voltage range selection and outputvoltage clamping. Extremely low RDS(ON) of the integrated protection N-channel FET helps toreduce power loss during the normal operation. Programmable soft-start time controls the slew rateof the output voltage during the start-up time. Independent enable control allows the complicatedsystem sequencing control. It integrates the over-temperature protection shutdown andautorecovery with hystersis

    标签: pw1555

    上传时间: 2022-02-14

    上传用户:

  • 基于AT89C52的农业温湿度智能控制系统设计

    设计了农业温湿度智能控制系统,该系统采用DHT11温湿度传感器作为温湿度采集模块,单片机选用AT89C52代替并调用Virtual terminal模拟串口通信,LCD1604液晶显示器实时显示温湿度,实现了温湿度的测量、显示,可自动控制加热、降温、加湿、通风,实现温湿度控制以及超限报警处理,并利用Proteus与Keil进行实际电路的仿真。试验表明,该系统实现了可靠的温湿度监控。We described the design of an intelligent control system of agriculture temperature and humidity.The system uses DHT11 temperature and humidity sensor as the temperature and humidity acquisition module.The SCM adopts AT89C52 to replace and call the virtual terminal for simulating serial communication.LCD1604 displays temperature and humidity in real time,which implements the measurement and display of temperature and humidity.The system is able to automatically control heating,cooling,humidification and ventilation,to achieve temperature and humidity control and over-Limit alarm processing.The system also uses Proteus and Keil for actual circuit simulation.The experiment shows that the system is capable of reliable temperature and humidity monitoring.

    标签: at89c52 温湿度智能控制系统

    上传时间: 2022-03-26

    上传用户:aben