{"id":387,"date":"2015-08-08T14:42:00","date_gmt":"2015-08-08T14:42:00","guid":{"rendered":"http:\/\/machineryequipmentonline.com\/video-equipment\/uncategorized\/power-supply-systemszener-stabilisation-and-series-and-shunt-regulators\/"},"modified":"2015-08-08T14:42:00","modified_gmt":"2015-08-08T14:42:00","slug":"power-supply-systemszener-stabilisation-and-series-and-shunt-regulators","status":"publish","type":"post","link":"http:\/\/machineryequipmentonline.com\/video-equipment\/power-supply-systemszener-stabilisation-and-series-and-shunt-regulators\/","title":{"rendered":"POWER SUPPLY SYSTEMS:ZENER STABILISATION AND SERIES- AND SHUNT-REGULATORS."},"content":{"rendered":"<div class=\"ekidk6a0dbb7c3366a\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '61e5902552e2353963d8d2f1bd1f4a8f',\n\t\t'format' : 'iframe',\n\t\t'height' : 250,\n\t\t'width' : 300,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/61e5902552e2353963d8d2f1bd1f4a8f\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.ekidk6a0dbb7c3366a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.ekidk6a0dbb7c3366a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.ekidk6a0dbb7c3366a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.ekidk6a0dbb7c3366a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.ekidk6a0dbb7c3366a {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<h5 align=\"justify\">ZENER STABILISATION<\/h5>\n<p align=\"justify\">The simplest form of voltage stabiliser is shown in Fig. 11.1(a), and consists of a series resistor and zener diode, which device has a sharp knee in its reverse voltage\/current characteristic. Output voltage remains at this <i>z<\/i><i>ener <\/i>point for a wide range of diode currents. If the load is so great that the diode runs out of current, stabilisation breaks down. The most common application of this simple principle is in the provision of a stabilised tuning voltage for varicap tuners. Here the zener diode takes the form of a two-terminal IC (example ZTK33B) with built-in thermal compensation; unlike a simple zener, these devices have virtually zero temperature coefficient. <\/p>\n<h5 align=\"justify\">SERIES- AND SHUNT-REGULATORS<\/h5>\n<p align=\"justify\">In situations of varying load and\/or supply voltage it is easy to arrange an absorption circuit to fully compensate for variations in <\/p>\n<p align=\"justify\"><a href=\"http:\/\/lh3.googleusercontent.com\/-6W4hKW0bwuA\/VcYVJCCOdpI\/AAAAAAAB0_U\/-HmMm117x2Q\/s1600-h\/POWER%252520SUPPLY%252520SYSTEMS-0140%25255B2%25255D.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-bottom: 0px; border-left: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top: 0px; border-right: 0px; padding-top: 0px\" title=\"POWER SUPPLY SYSTEMS-0140\" border=\"0\" alt=\"POWER SUPPLY SYSTEMS-0140\" src=\"http:\/\/lh3.googleusercontent.com\/-EY6ukwRxsII\/VcYVQThkDwI\/AAAAAAAB0_c\/CzBMu3edxmg\/POWER%252520SUPPLY%252520SYSTEMS-0140_thumb.jpg?imgmax=800\" width=\"244\" height=\"134\" \/><\/a> <\/p>\n<p align=\"justify\">supply and demand. The shunt regulator (Fig. 11.1(b)) is connected <i>ac<\/i><i>r<\/i><i>os<\/i><i>s <\/i>the load and this combination is fed from the unstabilised sup- ply; the series resistor R may be a physical component, but more usu- ally is formed by the source impedance of the supply. The current \ufb02owing in the shunt transistor is regulated at its base to maintain constant voltage across its c\u2212e terminals. <\/p>\n<p align=\"justify\">Less wasteful of energy is the series regulator, outlined in Fig. 11.1(c). Here the control transistor is in series with the load and alters its resistance to match the demand of the load, again maintaining constant output voltage. <\/p><div class=\"rxjbj6a0dbb7c3383a\" ><script async src=\"https:\/\/pagead2.googlesyndication.com\/pagead\/js\/adsbygoogle.js?client=ca-pub-0778475562755157\"\n     crossorigin=\"anonymous\"><\/script>\n<!-- 300x600 television-and-video -->\n<ins class=\"adsbygoogle\"\n     style=\"display:inline-block;width:300px;height:600px\"\n     data-ad-client=\"ca-pub-0778475562755157\"\n     data-ad-slot=\"6549443290\"><\/ins>\n<script>\n     (adsbygoogle = window.adsbygoogle || []).push({});\n<\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.rxjbj6a0dbb7c3383a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.rxjbj6a0dbb7c3383a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.rxjbj6a0dbb7c3383a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.rxjbj6a0dbb7c3383a {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.rxjbj6a0dbb7c3383a {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n<div class=\"qgook6a0dbb7c3375b\" ><script type=\"text\/javascript\">\n\tatOptions = {\n\t\t'key' : '0c1eb4c533eaedb7b996f49a5a4983a9',\n\t\t'format' : 'iframe',\n\t\t'height' : 300,\n\t\t'width' : 160,\n\t\t'params' : {}\n\t};\n<\/script>\n<script type=\"text\/javascript\" src=\"\/\/www.highperformanceformat.com\/0c1eb4c533eaedb7b996f49a5a4983a9\/invoke.js\"><\/script><\/div><style type=\"text\/css\">\r\n@media screen and (min-width: 1201px) {\r\n.qgook6a0dbb7c3375b {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 993px) and (max-width: 1200px) {\r\n.qgook6a0dbb7c3375b {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 769px) and (max-width: 992px) {\r\n.qgook6a0dbb7c3375b {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (min-width: 768px) and (max-width: 768px) {\r\n.qgook6a0dbb7c3375b {\r\ndisplay: block;\r\n}\r\n}\r\n@media screen and (max-width: 767px) {\r\n.qgook6a0dbb7c3375b {\r\ndisplay: block;\r\n}\r\n}\r\n<\/style>\r\n\n<p align=\"justify\">A practical circuit for a series regulator, as typically used in a port- able TV, is given in Fig. 11.2. The regulator element is <i>pnp <\/i>power transistor VT201. Its voltage source is the dotted box, representing a mains transformer\/recti\ufb01er\/capacitor ensemble, or a 12 V car bat- tery. At switch-on conduction in VT201 is established by c\u2212e current via VT202, itself turned on by base current from VT203 and \u2018kick- start\u2019 components C201 and W201. Voltage appears on the collector of VT201 then, and is potted down in R204\/205\/206 for application to the base of comparator transistor VT203. This transistor\u2019s emitter is held at a steady voltage of 4.7 by zener W202 and resistor R207. VT203 collector provides an error voltage to drive a proportional current into VT202 base. This latter device behaves as a current <\/p>\n<p align=\"justify\"><a href=\"http:\/\/lh3.googleusercontent.com\/-HvZVjjYpGa4\/VcYVSQcP_RI\/AAAAAAAB0_k\/Kr7spEb9bUg\/s1600-h\/POWER%252520SUPPLY%252520SYSTEMS-0141%25255B2%25255D.jpg\"><img decoding=\"async\" loading=\"lazy\" style=\"background-image: none; border-bottom: 0px; border-left: 0px; margin: 0px auto; padding-left: 0px; padding-right: 0px; display: block; float: none; border-top: 0px; border-right: 0px; padding-top: 0px\" title=\"POWER SUPPLY SYSTEMS-0141\" border=\"0\" alt=\"POWER SUPPLY SYSTEMS-0141\" src=\"http:\/\/lh3.googleusercontent.com\/-kEHOgWaNG1c\/VcYVUj2f1qI\/AAAAAAAB0_s\/hsDsjrMej3c\/POWER%252520SUPPLY%252520SYSTEMS-0141_thumb.jpg?imgmax=800\" width=\"237\" height=\"234\" \/><\/a> <\/p>\n<p align=\"justify\">ampli\ufb01er, steering the base current in regulator VT201. Output volt- age is trimmed by preset R205. <\/p>\n<p align=\"justify\">Imagine a bright picture tending to pull down the 11.3 V supply line. As it falls, VT203 (<i>pnp<\/i>) base voltage falls to <i>increase <\/i>its collector current, which increases VT202 base current. VT202 collector current increases as a result, and since all of it \ufb02ows through the base of regulator VT201, the latter is turned harder on to supply the extra current demand and restore the correct 11.3 V line voltage. Many such d.c. regulator circuits can respond up to and beyond 100 Hz rate, and the regulating mechanism described above can work on a \u2018sawtooth\u2019 basis to eliminate hum-ripple from a \u2018coarse\u2019 mains- derived supply. By the same token, it can absorb ripple induced on the supply line by timebase or audio output stages.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>ZENER STABILISATION The simplest form of voltage stabiliser is shown in Fig. 11.1(a), and consists of a series resistor and zener diode, which device has a sharp knee in its reverse voltage\/current characteristic. Output voltage remains at this zener point for a wide range of diode currents. If the load is so great that the [&hellip;]<br \/><a href=\"http:\/\/machineryequipmentonline.com\/video-equipment\/power-supply-systemszener-stabilisation-and-series-and-shunt-regulators\/\" class=\"more-link\" >Continue reading&#8230;<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[1],"tags":[],"aioseo_notices":[],"views":639,"_links":{"self":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/387"}],"collection":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/comments?post=387"}],"version-history":[{"count":0,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/posts\/387\/revisions"}],"wp:attachment":[{"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/media?parent=387"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/categories?post=387"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/machineryequipmentonline.com\/video-equipment\/wp-json\/wp\/v2\/tags?post=387"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}