1 #+TITLE: Alternative (and incompatible) layout for USB connectors
2 #+author: Svjatoslav Agejenko
5 * (document settings) :noexport:
6 ** use dark style for TWBS-HTML exporter
7 #+HTML_HEAD: <link href="https://bootswatch.com/3/darkly/bootstrap.min.css" rel="stylesheet">
8 #+HTML_HEAD: <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
9 #+HTML_HEAD: <script src="https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.3.5/js/bootstrap.min.js"></script>
10 #+HTML_HEAD: <style type="text/css">
11 #+HTML_HEAD: footer {background-color: #111 !important;}
12 #+HTML_HEAD: pre {background-color: #111; color: #ccc;}
16 + DISCLAIMER: I DO ELECTRONICS AND 3D DESIGN SOLELY AS A HOBBY. THERE
17 COULD BE ERRORS THAT CAN RESULT IN ALL KINDS OF DAMAGE. USE THESE
18 DESIGNS AT YOUR OWN RISK.
20 + This design is released under Creative Commons Zero (CC0) license.
24 - Homepage: https://svjatoslav.eu
25 - Email: [[mailto://svjatoslav@svjatoslav.eu][svjatoslav@svjatoslav.eu]]
30 - [[../../index.html][Other physical projects in this repository]]
31 - [[https://www.svjatoslav.eu/projects/][Other projects hosted at svjatoslav.eu]]
35 *Warning!* Here I describe a hack that I personally found useful for
36 my own needs. But it is dangerous. Not to be replicated unless you
37 know that you are doing.
42 I needed a way to power various devices I build.
49 - Popular and highly available.
50 - Ability to draw significant current directly from 12V cheap, popular
51 and powerful lead-acid battery (optionally off-grid). Useful for
52 powerful electric motors, heaters, soldering irons, radio
54 - Ability to draw limited but stabilized 5V power. Good for digital
56 - Ability to have limited and simple 1-wire digital communication.
58 USB Type A connectors are best match that I found.
60 The main problem is, I like USB connectors but I want to use different
61 and incompatible electrical layout with them.
63 *Connecting proper USB power supplies, devices and even cables to the
64 ones that use alternative electrical layout would do damage!!!*
66 To avoid accidental mismatches, I mark all connectors/cables and devices that
67 use alternative wiring with [[file:stickers.png][printed, laminated warning stickers]].
69 Alternative wiring schematic:
70 [[file:schematic.png]]
72 - Outer shell is ground.
73 - 2 central pins are re-purposed to deliver +12V and high power.
74 - 1 pin is for limited power +5V.
75 - 1 pin for 1-Wire data.
78 Example warning marking on device to indicate that alternative USB
81 [[file:../lab%20heater%20and%20cooler/make,%202.png]]