Thirdly , the principle in realization of d / a using on - chip pwm channel in the tms320f2812 - based system is analyzed . some methods of spwm , specially , nonsymmetry regular sampling are studied . avc system based on pwm technology is realized . finally , active vibration control experiment is performed about the first vibration mode of cantilever beam 三、研究了利用pwm通道实现da功能的工作原理,选用精度相对较高的不对称规则采样算法,利用dec2812设计并实现了基于脉宽调制技术的数模转换系统,完成了数据采集, ad转换, pwm波输出的全过程,并对转换结果进行了误差分析。
Device do not the put the many people to love video - disc machine , enlarger , tuner , few molds the conversion regard highly the to place , and this can cause the mutual interference , and particularly is a machine and to put the interference serious , can make the tone color the and produce suppress to feel . right of the way of doing put the device on the layering s stereo set 器材别叠放很多人爱将影碟机放大器调谐器数模转换器重叠放置，这会引起互相干扰，尤其是碟机与功放干扰严重，会使音色偏硬及产生压抑感。正确的做法是将器材放在分层的音响架上。
Firstly , a data acquisition circuit was designed , which is consisted of ad420 , dac702 and ad7701 . then , comparing with different usb control ics , an2131 was selected to achieve the control of data acquisition and usb communication . detailed rules to develop a usb device general purpose drivers were introduced , and the virtual instrument application software was developed basing on labview 首先是数据采集卡的制作,包括由ad420 、 dac702数模转换芯片构成的模拟输出通道,由ad7701 、 ad8200构成的模拟输入通道;然后比较几种不同的usb接口芯片,选择带usb接口的an2131微处理器实现数据采集的控制和usb传输功能;之后是usb设备驱动程序的开发和基于labview的虚拟仪器应用程序的设计。
Arithmetic figure that new dvd that conduct and actions world the adoption arithmetic figure of the first style see the port dvi port to broadcast , three stars the dvd - hd938 to can output to have not yet the compression to see the signal , but have no to need to pass by few molds the conversion process , from but avoided the loss of the painting quality with lose true , deliver the real arithmetic figure signal to television the dvi port is a high take the ieee1394 port breadth port , its deliver the speed to attain 5 gbps , is more than ten times to deliver the speed . at the same time , need not proceeding of port of adoption dvi few mold conversion , can avoid to convert what process result in to lose true , from but real realizes the arithmetic figure deliver 作为世界第一款采用数字视频端口dvi端口的新型dvd播放器，三星dvd - hd938能够输出未经压缩的数字视频信号，而无需经过数模转换过程，从而避免了画质的损失和失真，向电视传输真正的数字信号dvi端口是一种高带宽的端口，其传输速度达到5gbps ，是ieee1394端口传输速度的十几倍。同时，采用dvi端口不用进行数模转换，可以避免转化过程造成的失真，从而真正实现了数字传输。
The digital upward frequency conversion is the key element of the waveform synthesis . at the same time , basic theoretical analysis and optimum design are done for pci bus slave interface , fifo , transmit signal processor , digital - to - analog converter and logic control 本文对波形合成技术的核心? ?数字上变频进行了深入细致的研究和介绍，同时对波形合成器中的pci总线接口、先进先出缓冲器、发射信号处理、数模转换及逻辑控制等部分进行了分析和优化设计，给出了最佳设计方案。
In the seventh chapter , some of the above proposed new circuit , such as high frequency , high definition 12 - bit , 80mhz samples / s current - steering dac and fully differential r - mosfet - c bessel filter with accurate group delay , high accuracy bandgap reference and high drive capability cmos operational amplifier have been applied in communication gsm baseband i / o port integrated circuit , all the above blocks meet well with the design requirements of the system , and gain the better testing results , in the mean time , the above proposed high accuracy bandgap reference circuit als 第七章:将本文第二章提出的高速、高精度12位、 80mhz采样率电流舵结构的数模转换器和第五章提出的r一mosfet一c结构且具有精确群时延值的贝塞尔( bessel )滤波器以及第六章提出的高精度带隙基准电压源和高驱动能力全差分运算放大器电路应用于通信gsm基带输入/输出端口芯片，满足系统设计要求并取得了令人满意的实测结果。
This product is a full electron construction in which its front - end adopts pressure sensor with baffle filled oil chip . output signal is sent the data to microprocessor from high - precision , low temperature drift and high - reliability amplification circuit and a d convert circuit , after operating , to transform by high - precision d a convert circuit into standard signal output 该产品为全电子结构，前端采用带隔离膜充油芯体的压力传感器，输出信号由高精度低温漂和高可靠性的放大电路和模数转换电路将数据送入微处理器，经运算后由高精度数模转换电路变换为标准信号输出。
High definition digital to analog converter and high performance analog integrated filter among a practical system of communication , during the research work , we gain a lot of new high performance circuits of digital to analog converter and analog integrated filters with enhancement of high characteristics and realization of new structure circuit , which have been successfully applied in communication integrated circuits , and receives better practical application effect 本文紧跟国际学术研究热点，结合一实际通信系统中包括有上述基本单元电路，将对数模转换器、滤波器以及基准源电路的研究重点放在了其高性能指标的提高以及新结构电路的实现上，得到了一系列高性能特性的数模转换器、滤波器和基准电压源电路。
From computer directly , the device can get data from two specifically wav files which have double channels of data , and whose sample rate are 44100 , and whose resolution are 16 . then it makes digital signals convert into anolog signals and amplify them at the same time . at last , according to actual need , it can supply continuous anolog audio output of enough power and high fidelity at different speed 该设备可以直接从计算机获取两个双声道、 16位分辨率、 44100hz采样率的wav ( waveform )声音文件的数据,并同时将两个声音文件的数据进行数模转换和信号放大,最终以能满足实际生产需求的较高速率连续地输出具有足够驱动能力和高保真度的模拟信号,为终端高速磁带复录子机提供稳定可靠的音源。
In order to design a simple digital storage oscillograph under low price and high performance , on the basis of introducing the principle of simple digital storage ocsillograph , the project of simple digital storage ocsillograph is stuied , the d / a and signal display module of simple digital storage oscillograph is designed by the mcu and integrate circuit technology , the hardware block diagram provided in detail 摘要为了设计出一种价廉物美的简易数字存储示波器，在介绍简易数字存储示波器工作原理的基础上，对简易数字存储示波器的设计方案进行了研究，并采用单片机和集成电路技术，对该简易数字存储示波器的信号显示模块进行了设计，具体给出了数模转换器和信号显示模块的硬件电路图。
