{"id":386,"date":"2018-04-06T10:26:21","date_gmt":"2018-04-06T10:26:21","guid":{"rendered":"https:\/\/www.tina.com\/resources\/?page_id=386"},"modified":"2018-07-04T14:14:17","modified_gmt":"2018-07-04T14:14:17","slug":"3-the-non-inverting-amplifier","status":"publish","type":"page","link":"https:\/\/www.tina.com\/resources\/home\/ideal-operational-amplifiers-2\/3-the-non-inverting-amplifier\/","title":{"rendered":"3. The Non-Inverting Amplifier"},"content":{"rendered":"<div class=\"top-navigation\">\n<div class=\"current-page\"><img decoding=\"async\" src=\"https:\/\/www.tina.com\/images\/resource\/people-location-30.png\" \/>CURRENT &#8211; 3. The Non-Inverting Amplifier<\/div>\n<div class=\"previous-page\"><a href=\"https:\/\/www.tina.com\/resources\/home\/2-the-inverting-amplifier\/\"><img decoding=\"async\" src=\"https:\/\/www.tina.com\/images\/resource\/leftarrow5.png\" \/>PREVIOUS- 2. The inverting amplifier<\/a><\/div>\n<div class=\"next-page\"><a href=\"https:\/\/www.tina.com\/resources\/home\/4-input-resistance-of-op-amp-circuits\/\">NEXT- 4. Input resistance of op-amp circuits<img decoding=\"async\" src=\"https:\/\/www.tina.com\/images\/resource\/rightarrow5.png\" \/><\/a><\/div>\n<div class=\"clear\"><\/div>\n<\/div>\n<p><script>\nfunction setStyle(){ \nheight = document.getElementsByClassName('entry-header')[0].clientHeight;\ndocument.getElementsByClassName('entry-header')[0].style.marginTop = height +\"px\";\ndocument.getElementsByClassName('top-navigation')[0].style.top = Math.round(-(height-20)*2) +\"px\";\n}\nsetStyle();\nwindow.onresize = function(event) {\nsetStyle();\n};\n<\/script><\/p>\n<p align=\"justify\"><strong><em><span style=\"font-size: 22px;\">The Non-Inverting Amplifier<\/span><\/em><\/strong><\/p>\n<p><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">The op-amp can be configured to produce either an inverted or non-inverted output. In the previous section we analyzed the inverting amplifier. We now repeat the analysis for the non-inverting amplifier, as shown in Figure (5).<\/span><\/span><\/p>\n<div id=\"attachment_155\" style=\"width: 301px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-155\" class=\"wp-image-155 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opamp-non-invertingamplifier.png\" alt=\"Ideal Operational Amplifier, Non-inverting Amplifier\" width=\"291\" height=\"159\" \/><p id=\"caption-attachment-155\" class=\"wp-caption-text\">Figure 5- Non-inverting amplifier<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">We analyze this using the basic properties of the ideal op-amp. Since the current through <em>R<sub>1<\/sub><\/em> is zero,<\/span><\/span><\/p>\n<div id=\"attachment_154\" style=\"width: 60px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-154\" class=\"wp-image-154 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opamp2-18.png\" alt=\"\" width=\"50\" height=\"25\" \/><p id=\"caption-attachment-154\" class=\"wp-caption-text\">(18)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">Writing a node equation at the <em>v<sub>&#8211;<\/sub><\/em> node yields,<\/span><\/span><\/p>\n<div id=\"attachment_157\" style=\"width: 118px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-157\" class=\"wp-image-157 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opamp2-19.png\" alt=\"\" width=\"108\" height=\"44\" \/><p id=\"caption-attachment-157\" class=\"wp-caption-text\">(19)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">We set <em>v<sub>+<\/sub> = v<sub>&#8211;<\/sub><\/em>, and substitute for <em>v<sub>&#8211;<\/sub><\/em> to obtain,<\/span><\/span><\/p>\n<div id=\"attachment_158\" style=\"width: 118px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-158\" class=\"wp-image-158 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opamp2-20.png\" alt=\"\" width=\"108\" height=\"44\" \/><p id=\"caption-attachment-158\" class=\"wp-caption-text\">(20)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">The non-inverting gain is then given by,<\/span><\/span><\/p>\n<div id=\"attachment_159\" style=\"width: 90px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-159\" class=\"wp-image-159 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opamp2-21.png\" alt=\"\" width=\"80\" height=\"44\" \/><p id=\"caption-attachment-159\" class=\"wp-caption-text\">(21)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">We analyzed multiple-input inverting op-amps in previous Section (&#8220;The Inverting Amplifier&#8221;). We now analyze non-inverting op-amps with multiple inputs.<\/span><\/span><\/p>\n<div id=\"attachment_186\" style=\"width: 310px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-186\" class=\"wp-image-186 size-medium\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/TwoNon-InvertingInputs-300x148.png\" alt=\"Ideal Operational Amplifier\" width=\"300\" height=\"148\" srcset=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/TwoNon-InvertingInputs-300x148.png 300w, https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/TwoNon-InvertingInputs.png 311w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><p id=\"caption-attachment-186\" class=\"wp-caption-text\">Figure 6- Two non-inverting inputs<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">Figure (6)\u00a0 illustrates a circuit with two input voltages.\u00a0To find <em>v<sub>+<\/sub><\/em>, we apply Kirchhoff\u2019s current law to the non-inverting input terminal to yield (recall that the input current to the op-amp is zero),<\/span><\/span><\/p>\n<div id=\"attachment_188\" style=\"width: 130px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-188\" class=\"wp-image-188 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opampcircuit2-22.png\" alt=\"\" width=\"120\" height=\"42\" \/><p id=\"caption-attachment-188\" class=\"wp-caption-text\">(22)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">Solving then for <em>v<sub>+<\/sub><\/em>, we obtain<\/span><\/span><\/p>\n<div id=\"attachment_189\" style=\"width: 151px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-189\" class=\"wp-image-189 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opampcircuit2-23.png\" alt=\"\" width=\"141\" height=\"48\" \/><p id=\"caption-attachment-189\" class=\"wp-caption-text\">(23)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">The inverting voltage, <em>v<sub>&#8211;<\/sub><\/em>, is found from the node equation at <em>v<sub>&#8211;<\/sub><\/em> with the result,<\/span><\/span><\/p>\n<div id=\"attachment_191\" style=\"width: 130px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-191\" class=\"wp-image-191 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opampcircuit2-24.png\" alt=\"\" width=\"120\" height=\"44\" \/><p id=\"caption-attachment-191\" class=\"wp-caption-text\">(24)<\/p><\/div>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">Setting <em>v<sub>+<\/sub><\/em> equal to <em>v<sub>&#8211;<\/sub><\/em>, we obtain <\/span><\/span><\/p>\n<div id=\"attachment_192\" style=\"width: 211px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-192\" class=\"wp-image-192 size-full\" src=\"https:\/\/www.tina.com\/resources\/wp-content\/uploads\/2018\/03\/Opampcircuit2-25.png\" alt=\"\" width=\"201\" height=\"48\" \/><p id=\"caption-attachment-192\" class=\"wp-caption-text\">(25)<\/p><\/div>\n<h6><em><strong><u>APPLICATION<\/u><\/strong><\/em><\/h6>\n<p>Analyze the following circuit using circuit simulation with TINACloud to determine\u00a0V<em><sub>out<\/sub><\/em>\u00a0in terms of the input voltages by clicking the link below.<\/p>\n<p><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5b0faa6146753:959838&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\"><em><strong><span style=\"color: #466ce0;\"><em><strong>1-Two Non-inverting Inputs Circuit Simulation<\/strong><\/em><\/span><\/strong><\/em><\/a><span style=\"font-size: medium;\"><br \/>\n<\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">In a practical sense, it is important to briefly consider the effects of <em>loading<\/em> on the op-amp. The method we have been using for analysis yields the correct voltage gain, \u00a0based on the assumption that the current required from the dependent source of the <em>ideal<\/em> op-amp model is within the range set forth by the manufacturer&#8217;s data sheet for a <em>real<\/em> op-amp. Although we explore the practical considerations in later chapters, the next two examples illustrate the concept.<\/span><\/span><\/p>\n<p align=\"justify\"><span style=\"font-family: Bodoni MT, serif;\"><span style=\"font-size: large;\">When analyzing both the inverting and the non-inverting configurations, we must be certain that the op-amp is capable of supplying sufficient current to drive the load resistor.<\/span><\/span><\/p>\n<h6><em><strong><u>APPLICATIONS<\/u><\/strong><\/em><\/h6>\n<p>Analyze the following circuits using the TINACloud online circuit simulator to determine\u00a0V<em><sub>out<\/sub><\/em>\u00a0in terms of the input voltages by clicking the links below.<\/p>\n<div style=\"clear: both;\"><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5afac3de9bc9a:339969&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\"><em><strong><span style=\"color: #466ce0;\"><em><strong>2- Non-inverting Amplifier Circuit Simulation <\/strong><\/em><\/span><\/strong><\/em><\/a><\/div>\n<div><\/div>\n<div style=\"clear: both;\">\n<div style=\"clear: both;\"><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5afac66adf3ee:286983&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\"><em><strong><span style=\"color: #466ce0;\"><em><strong>3- Non-inverting Buffer Circuit Simulation<\/strong><\/em><\/span><\/strong><\/em><\/a><\/div>\n<div><\/div>\n<div style=\"clear: both;\">\n<div style=\"clear: both;\"><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5afacbc5231ab:938138&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\"><em><strong><span style=\"color: #466ce0;\"><em><strong>4- Non-inverting Input with Voltage Divider Circuit Simulation <\/strong><\/em><\/span><\/strong><\/em><\/a><\/div>\n<div><\/div>\n<div style=\"clear: both;\">\n<div style=\"clear: both;\"><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5afbe1e04f6a2:736453&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\"><em><strong><span style=\"color: #466ce0;\"><em><strong>5- Less than Unity Gain Circuit Simulation<\/strong><\/em><\/span><\/strong><\/em><\/a><\/div>\n<div><\/div>\n<div style=\"clear: both;\"><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5afbf29777264:968813&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\"><em><strong><span style=\"color: #466ce0;\"><em><strong>6- Non-inverting Summer with gain Circuit Simulation <\/strong><\/em><\/span><\/strong><\/em><\/a><\/div>\n<div><\/div>\n<div><\/div>\n<div style=\"clear: both;\"><em><strong><span style=\"color: #466ce0;\"><em><strong><a href=\"https:\/\/www.tinacloud.com\/tinademo\/tina.php?c=5afbeddf2f96d:222385&amp;amp;act;act=&amp;amp;noad&amp;amp;inframe=https%3A%2F%2Fwww.tina.com\" target=\"_blank\" rel=\"noopener\">7- Unity Gain Summer Circuit Simulation<\/a><\/strong><\/em><\/span><\/strong><\/em><\/div>\n<div><\/div>\n<div><\/div>\n<p>&nbsp;<\/p>\n<div class=\"previous-page\"><a href=\"https:\/\/www.tina.com\/resources\/home\/2-the-inverting-amplifier\/\"><img decoding=\"async\" src=\"https:\/\/www.tina.com\/images\/resource\/leftarrow5.png\" \/>PREVIOUS-2. The inverting amplifier<\/a><\/div>\n<div class=\"next-page\"><a href=\"https:\/\/www.tina.com\/resources\/home\/4-input-resistance-of-op-amp-circuits\/\/\">NEXT-4. Input Resistance of op-amp circuits<img decoding=\"async\" src=\"https:\/\/www.tina.com\/images\/resource\/rightarrow5.png\" \/> <\/a><\/div>\n<div class=\"clear\"><\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>CURRENT &#8211; 3. The Non-Inverting Amplifier PREVIOUS- 2. The inverting amplifier NEXT- 4. Input resistance of op-amp circuits The Non-Inverting Amplifier The op-amp can be configured to produce either an inverted or non-inverted output. In the previous section we analyzed the inverting amplifier. We now repeat the analysis for the non-inverting amplifier, as shown in [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":1357,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"yst_prominent_words":[29,253,260,274,276,266,262,272,168,265,263,267,268,292,270,275,269,264,261,277],"class_list":["post-386","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/pages\/386","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/comments?post=386"}],"version-history":[{"count":77,"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/pages\/386\/revisions"}],"predecessor-version":[{"id":3591,"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/pages\/386\/revisions\/3591"}],"up":[{"embeddable":true,"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/pages\/1357"}],"wp:attachment":[{"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/media?parent=386"}],"wp:term":[{"taxonomy":"yst_prominent_words","embeddable":true,"href":"https:\/\/www.tina.com\/resources\/wp-json\/wp\/v2\/yst_prominent_words?post=386"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}