{"id":69,"date":"2013-05-03T14:36:20","date_gmt":"2013-05-03T19:36:20","guid":{"rendered":"http:\/\/mikesmods.com\/mm-wp\/?p=69"},"modified":"2013-07-26T02:44:22","modified_gmt":"2013-07-26T07:44:22","slug":"hacking-the-ipad-3-lcd-part-3","status":"publish","type":"post","link":"http:\/\/mikesmods.com\/mm-wp\/?p=69","title":{"rendered":"Hacking the iPad 3 LCD, Part 3: First Layout"},"content":{"rendered":"

Much has happened since the last update.\u00a0 I have received a panel, as well as the balance of the components that I ordered.\u00a0 The panel has a half-inch scratch on the front, so hopefully it is still functional.<\/p>\n

The design has been steadily progressing.\u00a0 The architecture of the board is now a bit more complex – a Freescale Kinetis-L2 (ARM Cortex-M0+) processor is onboard, primarily because it was cheaper than the competing TI MSP430 that I had planned on using, go figure.\u00a0 To accompany this, a Mini-USB header has been added.\u00a0 This will not power the system as per other folks’ designs because I refuse to violate the USB spec (and my motherboard) that badly, but it will allow for connectivity to the host in order to (hopefully) enable control of the panel from keyboard hotkeys.\u00a0 A Linear Technology LT3502 switching regulator has been added to provide 3.3V for the panel and the processor, and a Skyworks AAT4618 high-side switch was put in place to allow power to the panel to be disabled when the system is inactive for greater power efficiency.\u00a0 The board should operate from something like 8 to 40V DC, for whatever power adapter you happen to have around that fits.<\/p>\n

\"First<\/a>

First run of the full-function interface board, revision A.\u00a0 I was too lazy to add some of the 3D models.\u00a0 For a sense of scale, the corner pads are sized for a 2-56 screw.<\/p><\/div>\n

So there it is.\u00a0 The board is now fully routed and has been sent out for manufacture.\u00a0 Naturally this means I’ve started noticing errors in it, but I’ve not found anything that means it altogether won’t work.\u00a0 Getting matched trace lengths on the mDP lines took a couple hours, and was probably the one most time consuming part of the design, but now all 8 lines are matched to within 10 mils.\u00a0 This is probably excessively close, but what the hell – as long as we’re doing it, may as well do it right.\u00a0 The final dimensions of the board ended up at 2.525 by 1.5 inches – quite a bit smaller than I originally planned on.\u00a0 And it is dense<\/em>.\u00a0 We’ll see how well everything works.<\/p>\n

(2013-05-07) I will not be releasing documents for this board for a while as I have noted a serious flaw in the processor section.\u00a0 I will use these for debugging the power system then respin the board when I am satisfied.<\/p>\n

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Much has happened since the last update.\u00a0 I have received a panel, as well as the balance of the components that I ordered.\u00a0 The panel has a half-inch scratch on the front, so hopefully it is still functional. The design has been steadily progressing.\u00a0 The architecture of the board is now a bit more complex […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"_links":{"self":[{"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=\/wp\/v2\/posts\/69"}],"collection":[{"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=69"}],"version-history":[{"count":10,"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=\/wp\/v2\/posts\/69\/revisions"}],"predecessor-version":[{"id":379,"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=\/wp\/v2\/posts\/69\/revisions\/379"}],"wp:attachment":[{"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=69"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=69"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/mikesmods.com\/mm-wp\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=69"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}