http://www.opencircuits.com/api.php?action=feedcontributions&user=67.188.87.137&feedformat=atomOpenCircuits - User contributions [en]2024-03-29T06:52:03ZUser contributionsMediaWiki 1.34.2http://www.opencircuits.com/index.php?title=User_talk:DavidCary&diff=3431User talk:DavidCary2007-05-07T23:04:50Z<p>67.188.87.137: </p>
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<div>Why don't you help finish my programmable chip eeg project and then use what you learned and the results to then create your own project. Programmers like to reuse working modulas instead of reinventing the wheel.<br />
<br />
<br />
<br />
==a talk through Wiki Howto==<br />
Hi DavidCary<br />
<br>Thank you very much you create this wiki to let us to share electronic projects. <br />
<br>I want to merge the "[[RS232 Dev Board]]" and "[[RS232 RS485 USB Converter Board]]", so want to discuss to the author, Tkb, of "RS232 Dev Board". However, i cannot find out the talk page like i talk to you by this way. Can you point me how to do it?<br />
<br>thanks<br />
<br>[[User:Yan|yan]]<br />
<br />
''If you have a question or comment specifically about the "RS232 Dev Board", please leave a comment on the [[RS232 Dev Board]] page or its "discussion" page.''<br />
''You can click on "[[User talk:Tkb]]" to leave a note on Tkb's user talk page.''<br />
''Since there are more people watching the "RS232 Dev Board" page than Tkb's page, you'll probably get a quicker response if you post to the "RS232 Dev Board" page than to Tkb's page.''<br />
''--[[User:DavidCary|DavidCary]] 20:00, 29 December 2006 (PST)''<br />
<br />
<br />
[[User:Chazegh|Chazegh]] created this "Open Circuits wiki".<br />
I am flattered that you think I had something to do with it.<br />
But since Chazegh seems to be too busy to spend much time here,<br />
it's up to you and I (and whoever else we can recruit) to create content here.<br />
--[[User:DavidCary|DavidCary]] 21:08, 29 December 2006 (PST)<br />
<br />
5.7.2007 Joe Silva:<br />
Hi David, great site! I've taken the liberty to remove some SPAM links from the pages. Yeah we sure do need an anti-valdalism bot. Also maybe not allow anonymous editing.</div>67.188.87.137http://www.opencircuits.com/index.php?title=User_talk:DavidCary&diff=3430User talk:DavidCary2007-05-07T23:04:26Z<p>67.188.87.137: /* a talk through Wiki Howto */</p>
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<div>Why don't you help finish my programmable chip eeg project and then use what you learned and the results to then create your own project. Programmers like to reuse working modulas instead of reinventing the wheel.<br />
<br />
<br />
<br />
==a talk through Wiki Howto==<br />
Hi DavidCary<br />
<br>Thank you very much you create this wiki to let us to share electronic projects. <br />
<br>I want to merge the "[[RS232 Dev Board]]" and "[[RS232 RS485 USB Converter Board]]", so want to discuss to the author, Tkb, of "RS232 Dev Board". However, i cannot find out the talk page like i talk to you by this way. Can you point me how to do it?<br />
<br>thanks<br />
<br>[[User:Yan|yan]]<br />
<br />
''If you have a question or comment specifically about the "RS232 Dev Board", please leave a comment on the [[RS232 Dev Board]] page or its "discussion" page.''<br />
''You can click on "[[User talk:Tkb]]" to leave a note on Tkb's user talk page.''<br />
''Since there are more people watching the "RS232 Dev Board" page than Tkb's page, you'll probably get a quicker response if you post to the "RS232 Dev Board" page than to Tkb's page.''<br />
''--[[User:DavidCary|DavidCary]] 20:00, 29 December 2006 (PST)''<br />
<br />
<br />
[[User:Chazegh|Chazegh]] created this "Open Circuits wiki".<br />
I am flattered that you think I had something to do with it.<br />
But since Chazegh seems to be too busy to spend much time here,<br />
it's up to you and I (and whoever else we can recruit) to create content here.<br />
--[[User:DavidCary|DavidCary]] 21:08, 29 December 2006 (PST)<br />
<br />
<br />
Hi David, great site! I've taken the liberty to remove some SPAM links from the pages. Yeah we sure do need an anti-valdalism bot. Also maybe not allow anonymous editing.</div>67.188.87.137http://www.opencircuits.com/index.php?title=User:DavidCary&diff=3429User:DavidCary2007-05-07T23:02:02Z<p>67.188.87.137: Removing SPAM links</p>
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<div>Welcome to my little corner of Open Circuits.<br />
<br />
I think I first stumbled across Open Circuits on 2006-03-01.<br />
I had been starting to set up a electronics-related wiki,<br />
but since this one was already here, why bother?<br />
<br />
Feel free to leave a note on [[User_talk:DavidCary|my talk page]].<br />
<br />
I created the [[WikiNode]].<br />
<br />
Electronic projects:<br />
''(Should I move these to dedicated pages such as [[electronics workbench]], etc.?)''<br />
<br />
== electronics workbench ==<br />
<br />
What exactly do I need for "normal" electronics development?<br />
I have a pile of stuff, and I have a wishlist of more stuff ...<br />
I hope to document which things are important to have, which things are useful but not immediately necessary, and which things ended up just gathering dust.<br />
<br />
== data collection network ==<br />
<br />
I'm building a "data collection network" that may end up with hundred of microcontroller sensor nodes,<br />
piping data into a PC.<br />
This may turn into a serious medical diagnosis tool.<br />
<br />
== POV display ==<br />
<br />
''(moved to [[POV display]])''<br />
<br />
== Full-color LED lighting ==<br />
<br />
I'm planning to build a silly little toy with 3 LEDs -- one for red, green, and blue --<br />
to show how "additive colors" work (a "color wheel").<br />
(I might just extend it to have a whole spectrum of visible and infrared LEDs, and a prism to show the little spikes in the spectrum that LEDs generate).<br />
<br />
"Red, Green, and Blue LED based white light generation"<br />
by Muthu, Schuurmans, and Pashley (2002)<br />
http://www.advancetransformer.com/uploads/resources/LED_White_Light_Issues</div>67.188.87.137http://www.opencircuits.com/index.php?title=Help:Contents&diff=3428Help:Contents2007-05-07T23:00:33Z<p>67.188.87.137: </p>
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<div><b>What the heck is this place?</b><br><br />
So Cina, Nate, and a guy named Aubry were all working on similar cellular projects using the GM862 but each project was different enough that we could not collaborate directly. However, we noticed that there was enough overlap between projects that certain things should be shared. Things like the audio biasing circuit, the power supply, and the footprint for various exotic parts. We wanted an easy way to share this information with others as well, and the concept of Open Circuits was born.<br><br><br />
<br />
We got the framework up (Cina is a pimp) in about 24hours. Even if you are completely new to Wikis, we're sure you'll find things fairly straight forward. Please use the following template (edit this change and copy/paste) into your posting as a starting point.<br><br />
<br />
----<br />
<br />
{| align=right<br />
|-<br />
| <br />
[[Image:Main-LT1528.jpg|LT1528]]<br />
|}<br />
<b>Description:</b><br> The LT1528 is a rather expensive regulator that is known for its fast transient response and high current output. Really its known because Telit recommends it for the GM862.<br />
<br />
<b>Documents:</b><br><br />
[[Media:LT1528.pdf|LT1528 Datasheet]]<br />
<br />
<b>Footprints:</b><br><br />
Coming in a minute from SFE. This regulator comes in two packages. The 5-DD is the SMD version, while the TO-220-5 is the through hole version.<br />
<br />
<b>Manufacturer Info:</b><br><br />
Linear part # : <br><br />
LT1528CQ (5-DD SMD Package)<br> <br />
LT1528CT (TO-220-5 PTH Package)<br />
<br />
<b>Supplier Info:</b><br><br />
Digikey part # : LT1528CQ-ND<br><br />
Single Piece Price : $7.13<br />
<br />
<b>Related Items:</b><br><br />
[[GM862 Cellular Module]]<br><br />
[[GM862 SMD Connector]]<br />
<br />
<b>Original Creator:</b> --[[User:Sparkfun|Sparkfun]] 22:18, 25 January 2006 (PST)</div>67.188.87.137http://www.opencircuits.com/index.php?title=Motor_driver&diff=3427Motor driver2007-05-07T22:59:46Z<p>67.188.87.137: </p>
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<div><br />
There are many kinds of motor drivers:<br />
* servo motor controller<br />
* stepper motor controller<br />
* DC motor controller ("brushed")<br />
* AC motor controller ("brushless")<br />
* ... (todo: fill in the other kinds) ...<br />
<br />
A DC motor controller that is 'reversable' generally uses an 'H bridge'. This 'H-bridge' uses four output drivers in a configuration that resembles an H where the load is the cross bar in the middle. The lines on either side of the load (the downward strokes in the H) represent a series connection of a pull-up driver and a pull-down driver. This allows each terminal of the load to be connected to either the positive supply rail, or the negative supply rail. This allows a positive, negative or zero voltage difference across the load. This load voltage is then utilised to provide the desired control required of the motor. The various combinations can give a 'forwards' torque on a DC motor, a 'backwards' torque on the same motor, can allow the motor to free-wheel (without any applied torque) or can provide a locking of the motor such that it resists any attempt to rotate it.<br />
<br />
A single phase AC motor is generally driven in the same way as a DC motor, however instead of operating the motor drive as a constant DC voltage (in either the 'forward' or 'reverse' direction) the AC motor is driven by an approximation to a sinewave. This approximation is created using the H bridge and driving it with a PWM input such that both the positive and negative voltage periods are the same. This is normally acheived either using a sawtooth waveform compared against a sine wave reference, or is done using a lookup table in a microcontroller.<br />
<br />
A similar method is used to drive multiphase (3-phase) AC motors, however instead of just using an H bridge, only a half H bridge is used per phase. Each phases half bridge is then driven in the same manner as for the single phase motor, with a phase difference between the phases as appropriate.<br />
<br />
((fill in more details here...))<br />
<br />
-----<br />
<br />
Some motor controller circuits are such that, if the software accidentally sets the "wrong" pins hi or lo, you get a short circuit through the output drivers. This will generally cause a high current to flow, due to the low on state resistance of the output drivers, which may destroy other electronic components before finally blowing the supply fuse.<br />
<br />
Other motor controller circuits are such that, if the software accidentally sets the "wrong" pins hi or lo, the worst that could happen is the motor spins the wrong way.<br />
These circuits are designed so that, no matter what the inputs, it is impossible to get a short circuit through the output drivers.<br />
Between "one branch on" and "the other branch on", there is a minimum "blanking time" which has "both branches off". This guarantees that we never have "both branches on" (short circuit).<br />
<br />
Guess which type of design I prefer?<br />
<br />
-----<br />
<br />
A random collection of semi-related links (please prune out the irrelevant ones):<br />
<br />
* [http://www.bobblick.com/techref/projects/hbridge/hbridge.html H-Bridge by Bob Blick]<br />
* [http://groups.yahoo.com/group/osmc/ the Open Source Motor Controller Project]<br />
* [http://massmind.org/techref/io/stepper/linistep/ LiniStepper] $30 each; Open Source! Circuit Diagram, PCB (Board) Layout, and PIC Software all available<br />
* [http://roko.ca/articles/hbridge.php H-Bridge Fundamentals] An in-depth article on the design of Mosfet H-Bridges<br />
* [http://PMinMO.com PMinMO.com] Open Source circuits and information on stepper motor controllers]<br />
* [http://www.epanorama.net/links/motorcontrol.html ePanorama] ePanorama Motor Control page<br />
<br />
Robots use motor drivers.<br />
* [http://glendale.edu/robotics_club/ Glendale robotics club] (Glendale CA)<br />
* [http://www.robotroom.com/HBridge.html "H bridges" by David Cook at the ROBOT ROOM(TM)]</div>67.188.87.137http://www.opencircuits.com/index.php?title=OpenCircuits:About&diff=3426OpenCircuits:About2007-05-07T22:59:12Z<p>67.188.87.137: </p>
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<div>Two beers, a hotel lobby, and some bad piano music. How else do these things start? No really.</div>67.188.87.137