The PW2228A is a high efficiency single inductor Buck-Boost converter which can supply theload current up to 1.5A. It provides auto-transition between Buck and Boost Mode. The PW2228Aoperates at 2.4MHz switching frequency in CCM. DC/DC converter operates at Pulse-Skipping Modeat light load. The output voltage is programmable using an external resistor divider, or is fixed to3.3V internally. The load is disconnected from the VIN during shutdown.The PW2228A is available in TDFN3X3-10 package.
标签： pw2228a
上传时间： 2022-02-11
上传用户：woyaotandang
PW2205 develops a high efficiency synchronous step-down DC-DC converter capable of delivering5A output current. PW2205 operates over a wide input voltage range from 4.5V to 30V andintegrates main switch and synchronous switch with very low RDS(ON) to minimize the conductionloss.PW2205 adopts the instant PWM architecture to achieve fast transient responses for high step downapplications and high efficiency at light loads. In addition, it operates at pseudo-constant frequencyof 500kHz under continuous conduction mode to minimize the size of inductor and capacitor
标签： pw2205
上传时间： 2022-02-11
上传用户：zinuoyu
The PW2163D is a high frequency, synchronous, rectified, step-down, switch-mode converter withinternal powerMOSFETs. It offers a very compact solution to provide a 3A continuous current over awide input supply range,with excellent load and line regulation.The PW2163D requires a minimal number of readily available, external components and is availablein a spacesaving SOT23-6 package
标签： pw2163d
上传时间： 2022-02-11
上传用户：yiyewumian
The PW2163 is a high efficiency 500 kHz synchronous step-down DC-DC converter capable ofdelivering 3A current. The PW2163 operates over a wide input voltage range from 4.5V to 18V andintegrates main switch and synchronous switch with very low RDS(ON) to minimize the conductionloss. Low output voltage ripple and small external inductor and capacitor sizes are achieved with 500kHz switching frequency. It adopts the instant PWM architecture to achieve fast transient responsesfor high step down applications
标签： pw2163
上传时间： 2022-02-11
上传用户：yiyewumian
The PW2053 is a high-efficiency monolithic synchronous buck regulator using a constantfrequency, current mode architecture. The device is available in an adjustable version. Supply currentwith no load is 40uA and drops to <1uA in shutdown. The 2.5V to 5.5V input voltage range makesthe PW2053 ideally suited for single Li-Ion battery powered applications. 100% duty cycle provideslow dropout operation, extending battery life in portable systems. PWM/PFM mode operationprovides very low output ripple voltage for noise sensitive applications. Switching frequency isinternally set at 1.2MHz, allowing the use of small surface mount inductors and capacitors. Lowoutput voltages are easily supported with the 0.6V feedback reference voltage
标签： pw2053
上传时间： 2022-02-14
上传用户：jason_vip1
5G通信系统中massive-MIMO-FBMC技术的结合概述摘要为了应对第五代移动通信（5G）中更高数据率和更低时延的需求，大规模MIMO （massive multiple-input multiple-output）技术已经被提出并被广泛研究。大规模 MIMO技术能大幅度地提升多用户网络的容量。而在5G中的带宽研究方面，特别 是针对碎片频谱和频谱灵活性问题，现有的正交频分多址（Orthogonal Frequency Division Multiplexing, OFDM）技术不可能应对未来的挑战，新的波形方案需要 被设计出来。基于此，FBMC（filter bank multicarrier）技术由于具有比OFDM低 得多的带外频谱泄露而被受到重视，并已被标准推进组IMT-2020列为5G物理层 的主要备选方案之一。 本文首先回顾了5G中波形设计方案（主要是FBMC调制）和大规模多天线系 统（即massive MIMO）的现有工作和主要挑战。然后，简要介绍了基于Massive MIMO的FBMC系统中的自均衡性质，该性质可以用于减少系统所需的子载波数 目。同时，FBMC中的盲信道跟踪性质可以用于消除massive MIMO系统中的导频 污染问题。尽管如此，如何将FBMC技术应用于massive MIMO系统中的误码率、 计算复杂度、线性需求等方面仍然不明确，未来更多的研究工作需要在massive MIMO-FBMC方面展开来。 关键词：大规模MIMO；FBMC；自均衡；导频污染；盲均衡
上传时间： 2022-02-25
上传用户：tigerwxf1
本系统采用电动机电枢供电回路串接采样电阻的方式来实现对小型直流有刷电动机的转速测量。该系统主要由二阶低通滤波电路,小信号放大电路、单片机测量显示电路、开关稳压电源电路等组成。同时自制电机测速装置,用高频磁环作为载体,用线圈绕制磁环,利用电磁感应原理检测电机运行时的漏磁,将变化的磁场信号转化为磁环上的感应电流。用信号处理单元电路将微弱电信号转化为脉冲信号,送由单片机检测,从而达到准确测量电机的速度的要求。In this system, the sampling resistance of armature power supply circuit is connected in series to measure the speed of small DC brush motor. The system is mainly composed of second-order low-pass filter circuit, small signal amplifier circuit, single-chip measurement and display circuit, switching regulated power supply circuit and so on. At the same time, the self-made motor speed measuring device uses high frequency magnetic ring as the carrier, coil winding magnetic ring, and electromagnetic induction principle to detect the leakage of magnetic field during the operation of the motor, which converts the changed magnetic field signal into the induced current on the magnetic ring. The weak electric signal is transformed into pulse signal by signal processing unit circuit, which is sent to single chip computer for detection, so as to meet the requirement of accurate measurement of motor speed.
标签： 直流电动机
上传时间： 2022-03-26
上传用户：hai7ying
本系统基于STM32单片机设计的非接触式电流检测控制系统,通过OPA548片将所给任意信号放大,由100Ω电阻和INA128芯片进行电流电压转换放大后,利用STM32单片机对获取的电压信号以0.488μs频率采样,利用STM32单片机的FFT库,获得信号的谐波信息。测量电流信号精准,该设计可广泛应用在以STM32单片机为核心控制器件的新型仪表中,性能精准且抗干扰能力强。This system is a non-contact current detection and control system based on STM32 single chip microcomputer. It amplifiesany signal through OPA548 chip, converts and amplifies the current and voltage by 100 Ω resistance and INA128 chip. The obtainedvoltage signal is sampled at the frequency of 0.488 μs by STM 32 single chip microcomputer, and the harmonic information of the signalis obtained by the FFT library of STM 32 single chip microcomputer. The measurement of current signal is accurate. This design can bewidely used in a new instrument with STM 32 single chip microcomputer as its core control device, with accurate performance and stronganti-interference capability.
上传时间： 2022-03-27
上传用户：tqsun2008
数字示波器功能强大,使用方便,但是价格相对昂贵。本文以Ti的MSP430F5529为主控器,以Altera公司的EP2C5T144C8 FPGA器件为逻辑控制部件设计数字示波器。模拟信号经程控放大、整形电路后形成方波信号送至FPGA测频,根据频率值选择采用片上及片外高速AD分段采样。FPGA控制片外AD采样并将数据输入到FIFO模块中缓存,由单片机进行频谱分析。测试表明:简易示波器可以实现自动选档、多采样率采样、高精度测频及频谱分析等功能。Digital oscilloscope is powerful and easy to use, but also expensive. The research group designed a low-cost digital oscilloscope, the chip of MSP430F5529 of TI is chosen as the main controller and the device of EP2C5T144C8 of Altera company is used as the logic control unit. Analog signal enter the programmable amplifier circuit, shaping circuit and other pre-processing circuit. The shaped rectangular wave signal is sent to FPGA for measure the frequency. According to the frequency value to select AD on-chip or off-chip high-speed AD for sampling. FPGA controls the off-chip AD sampling and buffers AD data by FIFO module. The single chip microcomputer receives the data, and do FFT for spectrum analysis. The test shows that the simple oscilloscope can realize automatic gain selection, sampling at different sampling rates, high precision frequency measurement and spectrum analysis.
上传时间： 2022-03-27
上传用户：突破自我
目的:自主研制一款超声手术刀电源控制系统,以减少能量的消耗,维持手术刀的正常温度。方法:对超声换能器在谐振附近的等效电路建立模型,并设计基于数字信号处理(DSP)的超声手术刀的硬件控制系统。结果:经对电源控制系统的电路和工作性能测试,生成的电流和电压的有效值等参数,能够及时调整电源的频率,并达到预期的功能指标,使超声手术刀工作在谐振状态。结论:以DSP为核心设计的超声手术刀电源控制系统,测试指标均能够达到预期的要求,能够使系统在谐振状态下工作。Objective: To independently develop a power control system of ultrasonic scalpel so as to reduce the energy consumption and maintain the normal temperature of ultrasonic scalpel. Methods: In this paper, the model of equivalent circuit of ultrasonic transducer nearby syntony was built up, and the hardware control system of ultrasonic scalpel based on digital signal processing(DSP) was designed. Results: Through testing the circuit and work performance of power control system, the series of parameters such as effective value and so on which were produced by this system could adjust frequency of power source in time and attain anticipative functional indicator, and it took the ultrasonic scalpel to work in syntonic situation. Conclusion: The tested indicators of power control system of ultrasonic scalpel based on the kernel design of DSP can attain anticipative requirement, and can take this system to work in syntonic situation.
上传时间： 2022-04-03
上传用户：bluedrops
