Fairchild Semiconductor - QVE00034   <link rel="stylesheet" href="/includes/css/newIdentity.css" type="text/css" media="screen, projection"/> <link rel="stylesheet" href="/includes/css/newNavigation.css" type="text/css" media="screen, projection"/>  <script type="text/javascript">qmad=new Object();qmad.bvis="";qmad.bhide="";</script>  <script type="text/JavaScript"> /******* Menu 0 Add-On Settings *******/ var a = qmad.qm0 = new Object(); /******* Keep Subs In window Add On ******/ a.subs_in_window_active = true; /******* Persistent States With Auto Open Subs Option Add On *******/ a.sopen_auto_enabled = true; </script> <script type="text/javascript" src="/includes/javascripts/navigation.js"></script>  <script language="javascript" type="text/javascript">function updateGoogleSearch(){document.csesearchbox.q.value = document.fscSearch.text.value;}</script>    </head> <body>  <div class="root"> <div class="leftbg"> <div class="rightbg" align="center"> <div class="leftShadow"> <div class="rightShadow"> <div class="boundry"> <div class="TopLinks"><a href="/cf/">Contact Us</a><a href="/my_fairchild/">My Fairchild</a><a href="/ShoppingExperience/action/viewShoppingCart">View Shopping Cart</a> <span class="TopLinks">Fairchild Worldwide:</span> <img src="/graphics/LangSelectEnglish.gif" border="0" align="absmiddle" usemap="#languageSelection" /></div> <div class="MainBanner"> <img src="/graphics/topBanner.jpg" border="0" usemap="#majorBanner" /></div> <div class="NavigationAndSearchBar"> <table width="980" border="0" cellspacing="0" cellpadding="0"> <tr> <td width="613"><ul id="qm0" class="qmmc"> <li><a class="qmstripe" href="/"><img class="qm-is qm-ia qm-ih" src="/graphics/openCubeNavigation/tab_products_and_samples.jpg" width="168" height="41"></a></li> <li><a class="qmparent" href="/index3.html"><img class="qm-is qm-ia qm-ih" src="/graphics/openCubeNavigation/tab_applications.jpg" width="128" height="41"></a> <ul> <li><a href="/markets/automotive/auto_app.html">Automotive</a></li> <li><a href="/markets/communications/dc-dc-typologies.html">Communications</a></li> <li><a href="/markets/computing/">Computing</a></li> <li><a href="/markets/consumer_electronics.html">Consumer</a></li> <li><a href="/markets/industrial.html">Industrial</a></li> <li><a href="/markets/lighting/">Lighting</a></li> <li><a href="/markets/motor/">Motor</a></li> <li><a href="/markets/ultraportable.html">Portable</a></li> <li><a href="/power/">Power</a></li> </ul> </li> <li><a class="qmparent" href="/index2.html"><img class="qm-is qm-ia qm-ih" src="/graphics/openCubeNavigation/tab_design_support.jpg" width="143" height="41"></a> <ul> <li><a href="/apnotes/">Application Notes</a> </li> <li><a href="/crossref/crossref.do">Cross Reference Search</a></li> <li><a class="qmparent" href="/designcenter/index.html">Design Tools</a> <ul> <li><a href="http://webdc.transim.com/fairchild/index.html">FETBench</a></li> <li><a href="/whats_new/offline_smps_toolkit.html">Off-Line SMPS Design</a></li> <li><a href="/whats_new/spm_tool.html">Motor-Drive Solutions</a></li> <li><a href="/whats_new/pfc_toolkit.html">Power Factor Correction</a></li> </ul> </li> <li><a href="/sitesearch/fsc.jsp?command=text&attr1=feb">Evaluation Boards</a></li> <li><a href="https://fairchildsemi.custhelp.com/cgi-bin/fairchildsemi.cfg/php/enduser/std_alp.php">Knowledge Base</a></li> <li><a class="qmparent" href="/models/index.html">Models</a> <ul> <li><a href="/models/HSPICE/Interface_and_Logic/">HSPICE (Interface & Logic)</a></li> <li><a href="/models/IBIS/Interface_and_Logic/">IBIS (Interface & Logic)</a></li> <li><a href="/models/PSPICE/Analog_and_Mixed_Signal/">PSPICE (Analog & Mixed Signal)</a></li> <li><a href="/models/PSPICE/Discrete/">PSPICE (Discrete)</a></li> <li><a href="/models/Pspice_Bsim3.1/Discrete/">PSPICE Bsim3.1 (Discrete)</a></li> <li><a href="/models/Saber/Discrete/">SABER (Discrete)</a></li> </ul> </li> <li><a class="qmparent" href="/onlineseminars/index.html">Online Seminars</a> <ul> <li><a href="/onlineseminars/serdes_seminar.html">Signal Path</a></li> <li><a href="/whats_new/pfc_toolkit.html">Power Factor Correction</a></li> <li><a href="/power/settopboxdvdonsem.html">Video</a></li> </ul> </li> <li><a href="/powerseminar/index.html">Power Seminars</a></li> <li><a href="/packaging/index.html">Packaging Information</a></li> <li><a class="qmparent" href="/company/quality.html">Quality & Reliability</a> <ul> <li><a href="/pcn/">PCN</a></li> </ul> </li> <li><a class="qmparent" href="javascript:void(0)">Search Tools</a> <ul> <li><a href="/crossref/crossref.do">Cross Reference Search</a></li> <li><a href="/packaging/topmark/index.html">Packaging Top Mark Search</a></li> <li><a href="/obsolete/obs.jsp">Obsolete Product Search</a></li> </ul> </li> </ul> </li> <li><a class="qmparent" href="/company/index.html" style="padding:0px;"><img class="qm-is qm-ia qm-ih" src="/graphics/openCubeNavigation/tab_company.jpg" width="87" height="41"></a> <ul> <li><a href="/company/index.html">About Fairchild</a></li> <li><a href="/whats_new/awards.html">Awards</a></li> <li><a href="/cf/">Contact Us</a></li> <li><a href="/careers/index.html">Careers</a></li> <li><a href="/company/ehs/">EHS</a></li> <li><a href="/tradeshow/index.html">Events</a></li> <li><a href="/company/green/index.html">Fairchild Green <img style="margin-left:6px;" src="/graphics/icons/greenlogo3.gif" alt="fairchild green" align="absmiddle" border="0"/></a></li> <li><a class="qmparent" href="http://investor.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-irhome">Investors</a> <ul> <li><a href="http://investor.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-homeprofile">Corporate Profile</a></li> <li><a href="/tradeshow/index.html">Events</a></li> <li><a href="http://governance.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-govhighlights">Governance</a></li> <li><a href="http://investor.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-irhome">Investor Relations</a></li> <li><a href="http://investor.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-stockchart">Stock Chart</a></li> <li><a href="http://investor.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-stockquote">Stock Quote</a></li> </ul> </li> <li><a class="qmparent" href="/company/media_center/index.html">Media Center</a> <ul> <li><a href="/whats_new/press_releases.html">Press Releases</a></li> </ul> </li> </ul> </li> <li class="qmclear"> </li> </ul></td> <td width="4"><img src="/graphics/invis.gif" width="2" height="39" /></td> <td width="355"><table width="100%" border="0" cellspacing="0" cellpadding="0"> <tr> <td><div class="search"> <form id="fscSearch" name="fscSearch" action="/sitesearch/fsc.jsp" method="get" style="margin:0px; padding:0px; background-color:transparent; background:none;"> <label>Search:</label> <input name="text" type="text" size="28" maxlength="58" onchange="updateGoogleSearch()" /> <input type="submit" class="buttons" value="Go" /> <input name="as" value="1" type="hidden" style="display:none" /> <input name="render" value="1" type="hidden" style="display:none" /> <input name="w" value="" type="hidden" style="display:none" /> <input name="command" value="text" type="hidden" style="display:none" /> <input name="attr1" value="" type="hidden" style="display:none" /> <input name="attr2" value="" type="hidden" style="display:none" />  <input name="t" value="0" type="hidden" style="display:none" />  <input name="i" value="sitemap id" type="hidden" style="display:none" /> <input name="ia" value="1" type="hidden" style="display:none" /> </form> </div></td> <td width="80"><div class="search"> <form action="http://www.fairchildsemi.com/googlesearchresults.html" name="csesearchbox" id="csesearchbox" style="margin:0px; padding:0px; background-color:transparent; background:none;"> <input name="sa2" type="submit" class="buttons" value="Google It!" /> <input type="hidden" name="cx" value="017491582235761852534:pbpv_2syzfq" style="display:none" /> <input type="hidden" name="cof" value="FORID:9" style="display:none" /> <input type="hidden" name="q" style="display:none" /> </form> </div></td> </tr> </table></td> </tr> </table> </div> <div class="body"> <div class="bodyBlueGreen"> <div class="breadcrumbs"> <a href="/" class="BClinktext">Home</a> > <a href="/products/" class="BClinktext">Find products</a> > <strong>QVE00034</strong></div> <div class="content"> <div class="rightSideBox" > <div class="title">Related Links</div> <div class="links"><a href="/products/">Find products</a> <a href="/technical_information/">Technical information</a> <a href="/samples/index.jsp">Request samples</a> <a href="/buy_products/order_products/">How to order products</a> <a href="/whats_new/press_releases.html">Press room</a> <a href="/cgi-bin/tsg.cgi">Support</a></div> </div>  <h1>QVE00034</h1> <p><span class="Bsubhead3"><a name="eff"></a>Power Efficiency</span></p> <p>The internal construction of the switch is based on subcomponents with a lens structure on both sides (emitter and detector). As a result, the flux of infrared light between the emitter and the detector is optimized and guarantees operational conditions compatible with low consumption and low voltage supply.</p> <p><span class="bsubhead3"><a name="aperture"></a>Aperture Width</span></p> <p>The switch features an aperture of 0.5mm on both sides (emitter and detector) centered on the optical axis of the device, which confines the useful infrared flux to a narrow beam between the emitter and the detector. This provides two essential benefits:<br> 1) Response sharpness: The output signal response to a knife edge moving in and out of the gap, vertically or horizontally (see fig.1 and fig.2 in the datasheet) changes from 10% to 90% for a 1mm displacement. That valve determines the resolution of the device, which is an important parameter in applications such as encoders.<br> 2) Immunity to parasitic light: The aperture blocks the side rays from the emitter and the resulting parasitic reflexions to he detector. This increases the noise level on the response and may contribute to false triggering.</p> <p><span class="bsubhead3"><a name="daylite"></a>Daylight Filter</span></p> <p>The detector is encapsulated in a daylight filtering resin that reduces the sensitivity of the device to ambient light. This also contributes to a lower noise level and a better signal-to-noise ratio. The result is an ability to operate at low input current, enhancing the low power consumption in the application.<p> <p><center><i>Typical Spectral Response</i></center><br> <img src="/graphics/daylite_curves_400x186.gif" width="400" height="186" alt="Typical Spectral Response"></p> <p><span class="bsubhead3"><a name="ops"></a>Operation</span></p> <p>This optical switch is designed to indicate the presence or absence of a vane or shield that has been placed in the emitter to detector path. Under normal or non-blocked operation the LED shines IR light on the phototransistor. This received light develops a photocurrent in the phototransistor. This photocurrent can be converted to a logic control indicating the aperture is not blocked. When a shield or other IR opaque material is used to interrupt the light path between the LED and the phototransistor, the phototransistor photocurrent is reduced to zero. This extremely small value of photocurrent can also be converted to a logic compatible signal indicating the optical path in the slot has been interrupted. This switch provides high mechanical sensitivity. Once the vane has moved to the center of the optical aperture a movement of only 0.5mm will cause the detector path to be interrupted.</p>  </div>  </div> </div> <div class="footer"> <div class="links"><span class="formatting"><a href="/">Products & Samples</a> | <a href="/index3.html">Applications</a> | <a href="/designcenter/">Design Support</a> | <a href="/company/">Company</a></span> <span class="formatting"><a href="/company/">About Fairchild Semiconductor</a> | <a href="/cf/">Contact Us</a> | <a href="http://investor.fairchildsemi.com/phoenix.zhtml?c=118532&p=irol-irhome">Investor Relations</a> | <a href="/whats_new/press_releases.html">Press Center</a> | <a href="/careers/">Careers</a> | <a href="/my_fairchild/index.html">MyFairchild</a> | <a href="/contents.html">Site Map</a></span><span class="formatting">© Copyright 2008 Fairchild Semiconductor Incorporated. All rights reserved. <a href="/company/privacy.html">Privacy Policy</a> | <a href="/legal/index.html">Site Terms & Conditions</a> | <a href="/legal/sale_terms_cond.html">Standard Terms & Conditions of Sale</a></span> </div> <div class="footerPowerLogo"><img src="/graphics/thePowerFranchiseLogo.gif" alt="The Power Franchise" width="123" height="57" /></div> <img src="/graphics/invis.gif" width="2" height="84"/> </div> </div> </div>  </div> </div> <div class="cleanFinish"></div> </div> </div> </div>  <map name="majorBanner" id="majorBanner"> <area shape="rect" coords="18,11,189,73" href="/index.html" /> <area shape="rect" coords="529,14,936,100" href="/company/green/index.html" /> </map> <map name="languageSelection" id="languageSelection"> <area shape="rect" coords="0,2,51,19" href="/" alt="English" /> <area shape="rect" coords="52,2,113,19" href="/cn/" alt="Chinese" /> <area shape="rect" coords="114,2,164,19" href="/jp/" alt="Japanese" /> <area shape="rect" coords="165,2,210,19" href="/kr/" alt="Korean" /> </map>  <script type="text/javascript">qm_create(0,false,0,500,false,false,false,false,false);</script>  <script type="text/javascript" src="http://www.google.com/coop/cse/brand?form=cse-search-box&lang=en"></script>  <script type="text/javascript"> var gaJsHost = (("https:" == document.location.protocol) ? "https://ssl." : "http://www."); document.write(unescape("%3Cscript src='" + gaJsHost + "google-analytics.com/ga.js' type='text/javascript'%3E%3C/script%3E")); </script> <script type="text/javascript"> var pageTracker = _gat._getTracker("UA-668903-7"); pageTracker._initData(); pageTracker._trackPageview(); </script> </body> </html>