{"id":47,"date":"2011-10-21T17:34:26","date_gmt":"2011-10-21T16:34:26","guid":{"rendered":"http:\/\/www.andrewwhyman.com\/blog\/?p=47"},"modified":"2011-10-21T17:34:26","modified_gmt":"2011-10-21T16:34:26","slug":"5v-l7805-regulator-heatsink","status":"publish","type":"post","link":"http:\/\/www.andrewwhyman.com\/blog\/electronics\/5v-l7805-regulator-heatsink\/","title":{"rendered":"5v L7805 Regulator Heatsink"},"content":{"rendered":"<p>A recent project of mine is creating my own 5v regulators for charging mobile phones, etc. This will be incorporated into a battery box which I and my friends use when camping. However on this years trip we burnt out the 5v regulator we were using. For that reason I decided to make my own that would be more robust in comparison.<\/p>\n<p>The biggest hurdle I&#8217;m hitting so far is dissipating enough heat away from the L7805 regulator (12v to 5v @ 1.5A). I am currently avoiding buying a &#8220;proper&#8221; heatsink for it as they cost in excess of \u00a33 each. The regulator itself cost about 15p! It has been suggested by a friend that I use a &#8220;buck&#8221; style regulator instead which is significantly more efficient and does not require as much heat dissipation. This will likely be what I look at if I can&#8217;t find a suitably cheap solution to this issue. However as those themselves cost almost \u00a33 each and require no heat sink in many cases it may be the better option.<\/p>\n<p>At the moment I have been using strips of aluminium attached to the 7805 regulator along with heat paste (the same kind used on computer CPU&#8217;s). It extracts the heat just fine but the aluminium on it&#8217;s own isn&#8217;t enough to keep the temperature low. The load I am using on the regulator is just a 25w peltier chip (it&#8217;s the device that keeps portable fridges cool). However as a friend pointed out it won&#8217;t be running at 25w because of the lower voltage.<\/p>\n<p>I have used 3 pieces of aluminium so far to extract the heat away and it seems to hold at a steady 90*c at 680mA, but as it&#8217;s not at full power, this is not going to be enough. I want to be able to extract at least 1A from it and still be below 90*c. A fan does aid this and keep it around 50*c but I&#8217;d prefer to omit the fan if possible.<\/p>\n<div style=\"margin: 10px auto; text-align: center;\"><a href=\"http:\/\/www.andrewwhyman.com\/blog\/wp-content\/uploads\/2011\/10\/IMG-20111021-00186.jpg\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.andrewwhyman.com\/blog\/wp-content\/uploads\/2011\/10\/IMG-20111021-00186-300x225.jpg\" alt=\"5v regulator with home made heatsink\" title=\"5v regulator with home made heatsink\" width=\"300\" height=\"225\" class=\"aligncenter size-medium wp-image-48\" srcset=\"http:\/\/www.andrewwhyman.com\/blog\/wp-content\/uploads\/2011\/10\/IMG-20111021-00186-300x225.jpg 300w, http:\/\/www.andrewwhyman.com\/blog\/wp-content\/uploads\/2011\/10\/IMG-20111021-00186.jpg 1024w\" sizes=\"auto, (max-width: 300px) 100vw, 300px\" \/><\/a><br \/>\n<img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.andrewwhyman.com\/blog\/wp-content\/uploads\/2011\/10\/IMG-20111021-00187-300x225.jpg\" alt=\"5v regulator current\" title=\"5v regulator current\" width=\"300\" height=\"225\" \/> <img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/www.andrewwhyman.com\/blog\/wp-content\/uploads\/2011\/10\/IMG-20111021-00189-300x225.jpg\" alt=\"5v regulator temperature (IN)\" title=\"5v regulator temperature (IN)\" width=\"300\" height=\"225\" \/><\/div>\n<p>I&#8217;m considering ordering one of the buck regulators (LM2575 by the way) for testing. However everywhere charges a fair bit for postage so I&#8217;ll wait until I need other parts too.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>A recent project of mine is creating my own 5v regulators for charging mobile phones, etc. This will be incorporated into a battery box which I and my friends use when camping. However on this years trip we burnt out the 5v regulator we were using. For that reason I decided to make my own [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"amp_status":"","footnotes":""},"categories":[14],"tags":[],"class_list":["post-47","post","type-post","status-publish","format-standard","hentry","category-electronics"],"_links":{"self":[{"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/posts\/47","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/comments?post=47"}],"version-history":[{"count":10,"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/posts\/47\/revisions"}],"predecessor-version":[{"id":60,"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/posts\/47\/revisions\/60"}],"wp:attachment":[{"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/media?parent=47"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/categories?post=47"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.andrewwhyman.com\/blog\/wp-json\/wp\/v2\/tags?post=47"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}