1 CN0295：灵活的4 mA至20 mA电压或电流驱动压力传感器变送器-德赢Vwin官网 网
×

CN0295：灵活的4 mA至20 mA电压或电流驱动压力传感器变送器

消耗积分:2 | 格式:pdf | 大小:311.32KB | 2021-03-23

从未拥有

分享资料个

This version (20 Jan 2021 02:00) was approved by erbe reyta.The Previously approved version (31 Jul 2017 02:10) is available.Diff

Table of Contents

CN0295: Flexible, 4 mA-to-20 mA Pressure Sensor Transmitter with Voltage or Current Drive

OVERVIEW

The circuit is a flexible current transmitter that converts the differential voltage output from a pressure sensor to a 4 mA-to-20 mA current output. The circuit is optimized for a wide variety of bridge-based voltage or current driven pressure sensors, utilizes only five active devices, and has a total unadjusted error of less than 1%. The power supply voltage can range from 7 V to 36 V depending on the component and sensor driver configuration. The input of the circuit is protected for ESD and voltages beyond the supply rail, making it ideal for industrial applications.

DEMO REQUIREMENTS

  • EVAL-CN0295-EB1Z circuit evaluation board
  • +7V to +24V power supply or equivalent power supply
  • Precision power supply
  • Agilent 3458A or equivalent Current meter
  • Differential Pressure sensor or Equivalent Dual channel DC Signal Source

HARDWARE SETUP

Power Supply

  • From +7V to +24V supply can be used to J2 for proper operation of the evaluation board
In order for the circuit to operate properly, the supply voltage, must be greater than 7 V in order to provide sufficient headroom.

Input Signal

Using Actual Sensor

  1. A differential output bridge type sensor should be attached to a 4 channel screw terminal block (J3) labeled with SUPPLYSNS on the PCB.
  2. A differential sensor gauge like from Honeywell or from NXP can be used for evaluation.
  • Vsense is where the analog voltage output of the sensor is being taken for measurement. Pin polarity should be take into account.
  • V/Iforce is the sensor excitation or is being supplied either from current or voltage source.
Pin polarity for Vsense and for V/Iforce should be take into consideration

Using Simulated input sensor

The following configuration can be used to simulate the sensor characteristic for evaluation purposes.

  1. A dual power supply can be used to power up the board from Vout1 and to generate a common-mode voltage of 2.5 V from Vout2 shown in the block diagram for test setup.
  2. A precision voltage source generates the 0 to 100 mV differential input voltage at the in-amp input, which then simulates the sensor output shown in the block diagram for test setup.
  3. 3 kΩ at R_bridge simulates the bridge type sensor impedance.

For lower than 5 kΩ bridge resistance, the drive voltage can be decreased down to 5 V using a buffer configuration by removing resistor R6.

Sensor Drive

The circuit can be switched to the current or voltage drive configuration by moving S1 to the position labeled on the PCB.

Voltage Drive Configuration

  • In the voltage drive mode with VDRIVE = 10 V, the supply voltage VLOOP or system supply must be greater than 10.2 V

Current Drive Configuration

  • In the current drive mode, the supply voltage VLOOP or system supply must be greater than 11.2 V in order to maintain sufficient headroom.
Current drive configuration can be used for four-wire ohm circuit configuration where in the main advantage of this configuration is that the voltage is measured directly across the load cell, neglecting the load effect of the lead wires for long distance measurements.
Both for voltage and current drive mode, the minimum loop supply voltage is dependent on the configuration of the drive circuit for the bridge.

Output Measurements

The output of the system can be measured in two ways, either through direct output current measurement or voltage output through the series resistor.

* Voltage Measurement

  • Voltage output measurement is done across a series 250ohms resistor though screw type terminal block (P1).
It is important that the 2-pin male header (J1) be populated first before doing a voltage measurement across the terminal block (P1)

* Current Measurement

  • Current output measurement is done by connecting the positive terminal of the current meter at one pin of the male header shunt terminal (J1) and the negative terminal of the meter connected to the other pin of the same male header shunt terminal.
The system has an onboard resistor load (R14) of 500ohms that can be de-soldered to replace with a desired resistor load value

SCHEMATICS, PCB LAYOUT, BILL OF MATERIALS

End of Document

下载并关注上传者 低至0.43元/天 开通VIP 免费下载

声明：本文内容及配图由入驻作者撰写或者入驻合作网站授权转载。文章观点仅代表作者本人，不代表德赢Vwin官网 网立场。文章及其配图仅供工程师学习之用，如有内容侵权或者其他违规问题，请联系本站处理。 举报投诉

评论(0)
发评论

下载排行榜

全部0条评论

快来发表一下你的评论吧 !

'+ '

'+ '

'+ ''+ '
'+ ''+ ''+ '
'+ ''+ '' ); $.get('/article/vipdownload/aid/'+webid,function(data){ if(data.code ==5){ $(pop_this).attr('href',"//www.hzfubeitong.com/m/login/index.html"); return false } if(data.code == 2){ //跳转到VIP升级页面 window.location.href="https://m.elecfans.com/vip/index?aid=" + webid return false } //是会员 if (data.code > 0) { $('body').append(htmlSetNormalDownload); var getWidth=$("#poplayer").width(); $("#poplayer").css("margin-left","-"+getWidth/2+"px"); $('#tips').html(data.msg) $('.download_confirm').click(function(){ $('#dialog').remove(); }) } else { var down_url = $('#vipdownload').attr('data-url'); isBindAnalysisForm(pop_this, down_url, 1) } }); }); //是否开通VIP $.get('/article/vipdownload/aid/'+webid,function(data){ if(data.code == 2 || data.code ==5){ //跳转到VIP升级页面 $('#vipdownload>span').text("开通VIP 免费下载") return false }else{ // 待续费 if(data.code == 3) { vipExpiredInfo.ifVipExpired = true vipExpiredInfo.vipExpiredDate = data.data.endoftime } $('#vipdownload .icon-vip-tips').remove() $('#vipdownload>span').text("VIP免积分下载") } }); }).on("click",".download_cancel",function(){ $('#dialog').remove(); }) var setWeixinShare={};//定义默认的微信分享信息，页面如果要自定义分享，直接更改此变量即可 if(window.navigator.userAgent.toLowerCase().match(/MicroMessenger/i) == 'micromessenger'){ var d={ title:'CN0295：灵活的4 mA至20 mA电压或电流驱动压力传感器变送器',//标题 desc:$('[name=description]').attr("content"), //描述 imgUrl:'https://'+location.host+'/static/images/ele-logo.png',// 分享图标,默认是logo link:'',//链接 type:'',// 分享类型,music、video或link，不填默认为link dataUrl:'',//如果type是music或video，则要提供数据链接，默认为空 success:'', // 用户确认分享后执行的回调函数 cancel:''// 用户取消分享后执行的回调函数 } setWeixinShare=$.extend(d,setWeixinShare); $.ajax({ url:"//www.hzfubeitong.com/app/wechat/index.php?s=Home/ShareConfig/index", data:"share_url="+encodeURIComponent(location.href)+"&format=jsonp&domain=m", type:'get', dataType:'jsonp', success:function(res){ if(res.status!="successed"){ return false; } $.getScript('https://res.wx.qq.com/open/js/jweixin-1.0.0.js',function(result,status){ if(status!="success"){ return false; } var getWxCfg=res.data; wx.config({ //debug: true, // 开启调试模式,调用的所有api的返回值会在客户端alert出来，若要查看传入的参数，可以在pc端打开，参数信息会通过log打出，仅在pc端时才会打印。 appId:getWxCfg.appId, // 必填，公众号的唯一标识 timestamp:getWxCfg.timestamp, // 必填，生成签名的时间戳 nonceStr:getWxCfg.nonceStr, // 必填，生成签名的随机串 signature:getWxCfg.signature,// 必填，签名，见附录1 jsApiList:['onMenuShareTimeline','onMenuShareAppMessage','onMenuShareQQ','onMenuShareWeibo','onMenuShareQZone'] // 必填，需要使用的JS接口列表，所有JS接口列表见附录2 }); wx.ready(function(){ //获取“分享到朋友圈”按钮点击状态及自定义分享内容接口 wx.onMenuShareTimeline({ title: setWeixinShare.title, // 分享标题 link: setWeixinShare.link, // 分享链接 imgUrl: setWeixinShare.imgUrl, // 分享图标 success: function () { setWeixinShare.success; // 用户确认分享后执行的回调函数 }, cancel: function () { setWeixinShare.cancel; // 用户取消分享后执行的回调函数 } }); //获取“分享给朋友”按钮点击状态及自定义分享内容接口 wx.onMenuShareAppMessage({ title: setWeixinShare.title, // 分享标题 desc: setWeixinShare.desc, // 分享描述 link: setWeixinShare.link, // 分享链接 imgUrl: setWeixinShare.imgUrl, // 分享图标 type: setWeixinShare.type, // 分享类型,music、video或link，不填默认为link dataUrl: setWeixinShare.dataUrl, // 如果type是music或video，则要提供数据链接，默认为空 success: function () { setWeixinShare.success; // 用户确认分享后执行的回调函数 }, cancel: function () { setWeixinShare.cancel; // 用户取消分享后执行的回调函数 } }); //获取“分享到QQ”按钮点击状态及自定义分享内容接口 wx.onMenuShareQQ({ title: setWeixinShare.title, // 分享标题 desc: setWeixinShare.desc, // 分享描述 link: setWeixinShare.link, // 分享链接 imgUrl: setWeixinShare.imgUrl, // 分享图标 success: function () { setWeixinShare.success; // 用户确认分享后执行的回调函数 }, cancel: function () { setWeixinShare.cancel; // 用户取消分享后执行的回调函数 } }); //获取“分享到腾讯微博”按钮点击状态及自定义分享内容接口 wx.onMenuShareWeibo({ title: setWeixinShare.title, // 分享标题 desc: setWeixinShare.desc, // 分享描述 link: setWeixinShare.link, // 分享链接 imgUrl: setWeixinShare.imgUrl, // 分享图标 success: function () { setWeixinShare.success; // 用户确认分享后执行的回调函数 }, cancel: function () { setWeixinShare.cancel; // 用户取消分享后执行的回调函数 } }); //获取“分享到QQ空间”按钮点击状态及自定义分享内容接口 wx.onMenuShareQZone({ title: setWeixinShare.title, // 分享标题 desc: setWeixinShare.desc, // 分享描述 link: setWeixinShare.link, // 分享链接 imgUrl: setWeixinShare.imgUrl, // 分享图标 success: function () { setWeixinShare.success; // 用户确认分享后执行的回调函数 }, cancel: function () { setWeixinShare.cancel; // 用户取消分享后执行的回调函数 } }); }); }); } }); } function openX_ad(posterid, htmlid, width, height) { if ($(htmlid).length > 0) { var randomnumber = Math.random(); var now_url = encodeURIComponent(window.location.href); var ga = document.createElement('iframe'); ga.src = 'https://www1.elecfans.com/www/delivery/myafr.php?target=_blank&cb=' + randomnumber + '&zoneid=' + posterid+'&prefer='+now_url; ga.width = width; ga.height = height; ga.frameBorder = 0; ga.scrolling = 'no'; var s = $(htmlid).append(ga); } } openX_ad(828, '#berry-300', 300, 250);