tag:blogger.com,1999:blog-11094420601458902822011-11-27T15:47:08.455-08:00fghttp://www.blogger.com/profile/15287570229904366978noreply@blogger.comBlogger41100tag:blogger.com,1999:blog-1109442060145890282.post-33607517742197297292010-01-06T05:54:00.000-08:002010-01-06T05:56:37.470-08:00<div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/1109442060145890282-3360751774219729729?l=itzone1.blogspot.com' alt='' /></div>fghttp://www.blogger.com/profile/15287570229904366978noreply@blogger.comtag:blogger.com,1999:blog-1109442060145890282.post-32160822409914123882010-01-06T05:52:00.001-08:002010-01-06T20:27:05.507-08:00<a href="http://itzone1.blogspot.com/2010/01/blog-post_06.html"><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://2.bp.blogspot.com/_pUZCqkVIFKs/S0SVxoKZlKI/AAAAAAAAAAc/GdlOcJasAFY/s1600-h/banner-girls.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 85px;" src="http://2.bp.blogspot.com/_pUZCqkVIFKs/S0SVxoKZlKI/AAAAAAAAAAc/GdlOcJasAFY/s320/banner-girls.png" border="0" alt=""id="BLOGGER_PHOTO_ID_5423624531088086178" /></a></a><div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/1109442060145890282-3216082240991412388?l=itzone1.blogspot.com' alt='' /></div>fghttp://www.blogger.com/profile/15287570229904366978noreply@blogger.comtag:blogger.com,1999:blog-1109442060145890282.post-13564000916410561722010-01-06T05:46:00.000-08:002010-01-06T05:48:18.840-08:00<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://4.bp.blogspot.com/_pUZCqkVIFKs/S0SUmQ9UCoI/AAAAAAAAAAU/836aVLOguyQ/s1600-h/5v-power-supply-by-l296.thumbnail.png"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 221px;" src="http://4.bp.blogspot.com/_pUZCqkVIFKs/S0SUmQ9UCoI/AAAAAAAAAAU/836aVLOguyQ/s320/5v-power-supply-by-l296.thumbnail.png" border="0" alt=""id="BLOGGER_PHOTO_ID_5423623236368992898" /></a><br /><br />This circuit is derived from an application note of L296, It is a Power Switching Regulator from ST. The advantage of using a switching regulator is that there is not much Heat Dissipation in this circuit.<div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/1109442060145890282-1356400091641056172?l=itzone1.blogspot.com' alt='' /></div>fghttp://www.blogger.com/profile/15287570229904366978noreply@blogger.comtag:blogger.com,1999:blog-1109442060145890282.post-62891984159276974792010-01-06T05:36:00.000-08:002010-01-06T05:46:12.642-08:00<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://4.bp.blogspot.com/_pUZCqkVIFKs/S0SUHJkt7KI/AAAAAAAAAAM/C1b-XZB1ApI/s1600-h/carlightimer.thumbnail.GIF"><img style="float:left; margin:0 10px 10px 0;cursor:pointer; cursor:hand;width: 320px; height: 215px;" src="http://4.bp.blogspot.com/_pUZCqkVIFKs/S0SUHJkt7KI/AAAAAAAAAAM/C1b-XZB1ApI/s320/carlightimer.thumbnail.GIF" border="0" alt=""id="BLOGGER_PHOTO_ID_5423622701810838690" /></a><br /><br />Pushbutton activated<br />Very simple circuitry<br /><br />Parts:<br /><br />R1______________4K7 1/4W Resistor<br />R2,R3___________1K 1/4W Resistors<br /><br />C1____________100µF 25V Electrolytic Capacitor (See Notes)<br /><br />D1___________1N4002 100V 1A Diode<br /><br />Q1____________BC547 45V 100mA NPN Transistor<br />Q2____________BC327 45V 800mA PNP Transistor<br /><br />P1_____________SPST Pushbutton<br /><br />RL1___________Relay with SPDT 10A min. switch<br />Coil Voltage 12V. Coil resistance 150-600 Ohms<br /><br /><br /><br />Pushing on P1 allows C1 charging to full 12V battery supply. Therefore Q1 is driven hard-on, driving in turn Q2 and its Relay load. The headlights are thus activated by means of the Relay contact wired in parallel to the vehicle’s headlights switch. RL1 remains activated until C1 is almost fully discharged, i.e. when its voltage falls below about 0.7V.<br />The timing delay of the circuit depends by C1 and R1 values and was set to about 1min. and 30sec.<br />In practice, due to electrolytic capacitors wide tolerance value, this delay will vary from about 1min. and 30sec. to 1min. and 50sec.<br />An interesting variation is to use the inside lamp as a command source for the timer. In this way, when the door is opened C1 is charged, but it will start to discharge only when the door will be closed, substituting pushbutton operation.<br />To enable the circuit acting in this way, simply connect the cathode of a 1N4002 diode to R1-C1 junction and the anode to the “live” lead of the inside lamp.<br />This lead can be singled-out using a voltmeter, as it is the lead where a 12V voltage can be measured in respect to the vehicle frame when the lamp is on.<div class="blogger-post-footer"><img width='1' height='1' src='https://blogger.googleusercontent.com/tracker/1109442060145890282-6289198415927697479?l=itzone1.blogspot.com' alt='' /></div>fghttp://www.blogger.com/profile/15287570229904366978noreply@blogger.com