{"id":9155,"date":"2014-01-08T17:29:25","date_gmt":"2014-01-09T01:29:25","guid":{"rendered":"http:\/\/rustybolt.info\/wordpress\/?p=9155"},"modified":"2014-01-09T10:38:04","modified_gmt":"2014-01-09T18:38:04","slug":"2014-01-08-dc-dc-converter-for-high-power-led","status":"publish","type":"post","link":"https:\/\/rustybolt.info\/wordpress\/?p=9155","title":{"rendered":"2014-01-08 DC-DC Converter For High Power LED"},"content":{"rendered":"<p>On eBay I bought a few of the LM2596 buck converters with constant current to use with the 10 watt LEDs I bought, and received them in the mail today.\u00a0 Now I don&#8217;t need a 1 or 2 ohm resistor at several watts to limit the current and waste power.\u00a0 Problem is it&#8217;s difficult to find info on the pots and indicator LEDs on the board.<\/p>\n<p><a href=\"http:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2014\/01\/IMG_20140109_093132S4.jpg\"><img loading=\"lazy\" decoding=\"async\" class=\"alignright size-medium wp-image-9162\" alt=\"IMG_20140109_093132S4\" src=\"http:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2014\/01\/IMG_20140109_093132S4-300x224.jpg\" width=\"300\" height=\"224\" srcset=\"https:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2014\/01\/IMG_20140109_093132S4-300x224.jpg 300w, https:\/\/rustybolt.info\/wordpress\/wp-content\/uploads\/2014\/01\/IMG_20140109_093132S4.jpg 800w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a>The PC board has three adjustable trimmer pots and three indicator LEDs.\u00a0 The auction gives information about adjusting for the voltage then shorting it with an ammeter and adjusting for the current.\u00a0 Problem is there is nothing &#8211; no labels, no part numbers &#8211; to indicate which trimpot or LED does what. For instance, it says &#8220;<span style=\"color: #242424; font-size: x-large;\"><span style=\"color: #000000; font-family: Trebuchet MS;\"><span style=\"font-family: Times; font-size: large;\"><span style=\"font-family: Trebuchet MS; font-size: large;\"><span style=\"font-size: small;\"><span style=\"color: #000000;\"><span style=\"color: #000000;\"><span style=\"color: #000000;\"><span style=\"color: #000000;\"><span style=\"color: #000000; font-size: small;\">The charge current of transfer lamp is default 0.1 times of the charging current (constant current value)<\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span><\/span>&#8221;\u00a0 I&#8217;m still trying to figure out what that means.<\/p>\n<p>I looked up the name on the back of the PC board and came up with nothing useful.\u00a0 In any case, I&#8217;ll have to do some experimenting with it and find out what&#8217;s what.<\/p>\n<p>Update Jan 8 &#8211; I found that the trimmer on the right (see pic) is the voltage adjust.\u00a0 The trimmer on the left seems to adjust current, but when I short circuited the output (according to the instructions) the current was sometimes limited, and sometimes it went up to the half amp maximum limit of the small power supply I was using for the test.\u00a0 This odd behavior could have been caused by the power supply.\u00a0 I&#8217;ll have to test it with a wall wart that can put out more than an amp.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>On eBay I bought a few of the LM2596 buck converters with constant current to use with the 10 watt LEDs I bought, and received them in the mail today.\u00a0 Now I don&#8217;t need a 1 or 2 ohm resistor at several watts to limit the current and waste power.\u00a0 Problem is it&#8217;s difficult to<a href=\"https:\/\/rustybolt.info\/wordpress\/?p=9155\"> <\/p>\n<p> (Read More&#8230;)<\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-9155","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/9155","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=9155"}],"version-history":[{"count":7,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/9155\/revisions"}],"predecessor-version":[{"id":9158,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=\/wp\/v2\/posts\/9155\/revisions\/9158"}],"wp:attachment":[{"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=9155"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=9155"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rustybolt.info\/wordpress\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=9155"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}