{"id":12,"date":"2007-12-16T15:14:30","date_gmt":"2007-12-16T20:14:30","guid":{"rendered":"http:\/\/www.logicalzero.com\/blog\/?p=12"},"modified":"2014-05-23T01:15:15","modified_gmt":"2014-05-23T05:15:15","slug":"a-whole-lotta-diode","status":"publish","type":"post","link":"http:\/\/www.logicalzero.com\/blog\/?p=12","title":{"rendered":"A whole lotta diode."},"content":{"rendered":"<p><img src=\"http:\/\/www.logicalzero.com\/blog\/images\/motorboard_diodes_thumb.jpg\" style=\"margin: 4px\" alt=\"Old diode size, new diode size.\" title=\"Old diode size, new diode size.\" align=\"left\" \/>I received my order from Electronics Goldmine late last week. It contained, among other things, a couple of items for the Motor Controller Project: several 3&#8243;x4&#8243; pieces of copper-clad board and twenty 1N5404 diodes (3A, 400V). I knew these were overkill, but I figured it was safer to err on the side of caution.<\/p>\n<p>What I hadn&#8217;t figured was the physical <em>size<\/em> of the new diode. In my original board layout, I&#8217;d used 1N4004 diodes, only because they were what I had on-hand. The 1N5404 are more than twice the width and time-and-a-half longer than I&#8217;d planned. I tried cramming one onto my mockup of the board (a printed copy on cardboard) and failed ridiculously.<\/p>\n<p>So: the board needed to be redesigned.<\/p>\n<p><!--more--><a href=\"http:\/\/www.logicalzero.com\/blog\/images\/motorboard2_bottom.png\"><img src=\"http:\/\/www.logicalzero.com\/blog\/images\/motorboard2_bottom_thumb.png\" style=\"margin: 4px\" alt=\"The revised layout of the motor controller board, bottom side.\" title=\"The revised layout of the motor controller board, bottom side.\" align=\"left\" \/><\/a>The copper-clad I ordered was larger than I needed for the original design; this worked to my advantage. With the extra space, the new board was easy to lay out. I decided to make the traces heavier, which also simplifies things. I still find Eagle frustrating, so I ended up doing a lot of touch-up in Photoshop. The most significant edit I made was reducing the diameter of the holes. I wanted to make them only tiny dots in the copper, much smaller than the hole, serving only as guides for the drill.<\/p>\n<p>The copper-clad is also double sided, something I hadn&#8217;t thought about. Rather than etch it all away, I&#8217;m going to try doing a double-sided board.<br clear=\"all\" \/><a href=\"http:\/\/www.logicalzero.com\/blog\/images\/motorboard2_top+place.png\"><img src=\"http:\/\/www.logicalzero.com\/blog\/images\/motorboard2_top+place_thumb.png\" style=\"margin: 4px\" alt=\"The top of the revised motor controller board with component placement.\" title=\"The top of the revised motor controller board with component placement.\" align=\"right\" \/><\/a>Most of the top has no functional purpose. I gave each hole a wide radius in order to account for misalignment between the sides. The connection to the first and last input (on the right side) was made via a jumper wire in the original design; I&#8217;m going to attempt running a trace on top. I can&#8217;t do a plated through-hole, so I&#8217;m planning to put wire through the hole, solder each side, then cut the wire flush with the solder blob. I&#8217;m not sure if this is the recommended way of doing a home-brew via, but it&#8217;s worth a shot. If things turn out badly in the etch, I&#8217;ll just revert to the jumper wire idea.<\/p>\n<p>Once I have access to a laser printer (i.e. the office on Monday), I&#8217;ll print a few copies on magazine paper. It seemed to work fairly well last time. If I see any smudging of the toner after the transfer, I&#8217;ll dissolve it with acetone and try again.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>I received my order from Electronics Goldmine late last week. It contained, among other things, a couple of items for the Motor Controller Project: several 3&#8243;x4&#8243; pieces of copper-clad board and twenty 1N5404 diodes (3A, 400V). I knew these were overkill, but I figured it was safer to err on the side of caution. What [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[5],"tags":[12,11],"_links":{"self":[{"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/12"}],"collection":[{"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=12"}],"version-history":[{"count":1,"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/12\/revisions"}],"predecessor-version":[{"id":797,"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/12\/revisions\/797"}],"wp:attachment":[{"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=12"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=12"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.logicalzero.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=12"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}