The PW5200A/ PW5200C is high efficiency synchronous, PWM step-up DC/DC converters optimizedto provide a high efficient solution to medium power systems. The devices work with a 1.4MHz fixedfrequency switching. These features minimize overall solution footprint by allowing the use of tiny,low profile inductors and ceramic capacitors. Automatic PWM/PFM mode switching at light loadsaves power and improves efficiency
标签： pw5200
上传时间： 2022-02-11
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PW2330 develops a high efficiency synchronous step down DC-DC converter capable of delivering3A output current. PW2330 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. PW2330 adopts the proprietary instant PWM architecture to achieve fast transient responsesfor high step down applications and high efficiency at light loads. In addition, it operates atpseudo-constant frequency of 500kHz under continuous conduction mode to minimize the size ofinductor and capacitor
标签： pw2330
上传时间： 2022-02-11
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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
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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
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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
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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
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
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数字频率计是电工电子中常用的测量仪器,数字频率计通过用输入待测信号对一特定长度的信号进行计数,从而得出频率并通过数码管直观的显示出来。本文提出了一种与输入同步的数字频率计的设计,提高了频率计的精度,设计采用Multisim软件进行设计和仿真的过程,介绍了其工作原理,硬件电路设计和仿真的过程。设计采用了Multisim软件进行设计和仿真,设计结果得到的验证。Digital frequency counter is used to measure the frequency of a signal.It is common to use a multivibrator to generate a standard 1 second time base signal and count input signal gated by this signal.However,the asynchronous of this time base signal with input signal will bring errors.In this paper,a high precision frequency counter which use synchronized time base signal generator is proposed.This frequency counter is designed and simulated by Multisim tools and result is verified.
标签： multisim
上传时间： 2022-05-08
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随着绿色工程的实施，在照明领域，已将电力电子技术广泛应用到电气照明中去，所以寻找绿色、高效、长寿命、光色好等优点的照明设备已成为必然。高强度气体放电灯(High-Intensity-Discharge)由于光效高而节能，已经在照明领域取得广泛的应用。但传统的电感镇流器存在诸多缺点，故与之配套的HID灯电子镇流器的开发成为研究的热点，本文对基于数字控制的HID灯电子镇流器进行了研究与设计。 本文第二章阐述了气体放电的基础知识和电光源的基本参数。比较了电子电感镇流器的优缺点，针对HID灯对电子镇流器的要求，介绍了电子镇流器基本原理和发展趋势。第三章对高强度气体放电灯的关键技术进行了研究。首先是对电子镇流器的拓扑结构进行分析与比较，选定了传统的三级结构进行设计，其次是对电子镇流器的核心-逆变器的结构进行了分析，选定了全桥逆变结构，再次是对HID灯的各种点火电路的结构进行分析，本文选定了用单片机进行控制的点火的方式；最后是对灯的声谐振进行了各种方式的比较与分析，给出通过数字调频的方式来抑制声谐振理论分析。第四章主要通过比较各种功率因数校正的优缺点，并采取了基于boost结构的临界功率因数校正。第五章对HID灯启动工作过程进行了分析，提出了三段线性控制的策略，给出了控制的理论分析;比较了间接和直接两种控制恒功率的方法，选定间接控制方式。第六章主要对数字控制的250W金卤灯的样机的实现中的部分电路(保护、驱动、逆变)进行分析与设计并给出了部分电路图和软件设计的流程图以及部分仿真与试验波形。最后在第七章对试验结果进行分析，对本文的设计进行小结以及对未来的展望。
上传时间： 2013-07-16
上传用户：heart_2007
近几年来，OFDM(Orthogonal Frequency Division Multiplexing)技术引起了人们的广泛注意，根据这项新技术，很多相关协议被提出来。其中WiMax(Wireless MetropolitanArea Networks)代表空中接口满足IEEE 802.16标准的宽带无线通信系统，IEEE标准在2004年定义了空中接口的物理层(PHY)，即802.16d协议。该协议规定数据传输采用突发模式，调制方式采用OFDM技术，传输速率较高且实现方便、成本低廉，已经成为首先推广应用的商业化标准。 本文主要对IEEE802.16d OFDM系统物理层进行研究，并在XILINX公司的Virtexpro II芯片上实现了基带算法。 首先讨论了OFDM基本原理及其关键技术。根据IEEE802.16d OFDM系统的物理层发送端流程搭建了基带仿真链路，利用MATLAB/SIMULINK仿真了OFDM系统在有无循环前缀(CP)、多径数目不同等情况下的性能变化。由于同步算法和信道估计算法计算量都很大，为了找到适合采用FPGA实现的算法，分析了同步误差和不同信道估计算法对接收信号的影响，并结合计算量的大小提出了一种新的联合同步算法，以及得出了LS信道估计算法最适合802.16d系统的结论。 其次，完成了基带发射机和接收机的FPGA硬件电路实现。为了使系统的时钟频率更高，采用了流水线的结构。设计中采用编写Verilog程序和使用IP核相结合的办法，实现了新的联合同步算法，并且通过简化结构，避免了信道估计算法中的繁琐除法。利用ISE9. 2i和Modelsim6.Oc软件平台对程序进行设计、综合和仿真，并将仿真结果和MATLAB软件计算结果相对比。结果表明，采用16位数据总线可达到理想的精度。 最后，采用串口通信的方式对基带系统进行了验证。通过串口通信从功能上表明该系统确实可行。 关键词：IEEE802. 16d； OFDM； 同步；信道估计；基带系统
上传时间： 2013-07-31
上传用户：1757122702
