On Wednesday, January 18, 2012 09:18:27 AM Erik Christiansen did opine: > On 18.01.12 00:59, gene heskett wrote: > > Well, the only marks on the package show on top of it and they are > > confusing. On about a 20x blowup of the pdf'd brochures page showing > > the pin names, it looks like this for a bottom view. > > > > led end sensor end > > > > |-------------------------------| > > | > > | K . .vcc | > > | > > | 0 .vo 0 | > > | > > | A . .gnd | > > | > > |-------------------------------| > > > > And the footprint in the library has both + terminals on the same > > side. > > If that's the library which I posted, then that's a misinterpreation, > AFAICT. Please remember that the schematic symbol conveys _no_ pin > location information. > Good in fact, I was under the impression that there was a hidden linkage between the schematic and the footprint.
> Gene, have you found this pinout issue in the board editor? (Click on > the 5th icon in the horizontal toolbar near the top of the schematic > editor) The library editor can also be used to check the physical > pinout, but that's harder to explain when you can't see my hand-waving. > > I'll attach a board and a schematic file which demonstrate that the > anode and vcc pins are in fact on opposite sides of the package. If you > copy the files into a separate new project, open the schematic, and say > yes to opening the board, the latter reveals the physical relationship > of these pins. I've placed one device on the underside of the PCB, so we > see a bottom view of the pins for that device. This is what I saw too. What I am mentally missing is the linkage between the schematic, and the terminals of the packages footprint which carry no labels, since in this application, the mechanical location of the device on the board is very important. After a lot of slogging around the encoder wheel with the calipers, and arrived at an ideal spacing between the individual devices of nominally .340" so the devices are effectively looking at every third hole in the disk. This should get me in the ballpark, and with 4-40 bolts to mount them being a little sloppy, and with just a somewhat oversized (1/8" hole in the pcb for the leads to be able to move a few thou when I loosen the bolts and pry one way or the other, I figure the timings of the AB outputs can be made pretty close to equal for all 4 phases. IOW I won't drill for the individual lead, they will all come thru the same 1/8" hole & be bent over & soldered, probably with a "J" profile so the device can move a few thou for pulse timing equality. I do have a bit of room to do the lead forming on the solder side, perhaps 3/8", but I had planned on putting the leds current limiter R, about 120-150 ohms, in the area between the led's "towers" as there is clearance between the moving gears at that point of perhaps 3/8". Use them for via's IOW. Then, and this is something I have not asked about just yet, the index pulse can also be placed such that it occurs in an AB state that would allow the CW or CCW edge of that pulse to be detected so that there is not a 4 degree ambiguity in where the pulse is recognized when the direction is reversed. In this case, it is not the pulse polarity that would be important, but the edge detection only being active if the correct AB state existed. I haven't worked out the Karnaugh map of that yet, and the docs in the integrator manual are not that specific. Probably not a show stopper since in reverse it is very unlikely any cutting will be done, but... > > And its this ambiguity in the docs on this stuff that cost me the last > > 3 of a different type device about 18 months go when I was gung ho to > > do this then, and it all smoked in about 10 milliseconds when I > > applied 5 volts. > > Yeah, this one lets the magic smoke out at reverse bias of only 3v on > the LED. Yup, about $25 worth. :( > If my interpretation of the Honeywell datasheet was wrong, it'll take me > less than a minute to swap pins. Probably not wrong, if in making the .brd, I can 'wire' it like its supposed to be. That I haven't tried yet. > It took me a while to get the hang of eagle. Each of these apps needs a > realignment of thinking, before it's straightforward. Understatement of the month. ;-) I think I am making progress, but have not attempted to convert the schematic to a .brd yet. I wanted to make sure I didn't do the smoke release a second time, and if there is not a hidden linkage between the schematic and the mechanical .brd image, I'll read and proceed. But today I have a termite company installing new, kill em all, baits. That is something else WV apparently has a surplus of, termites, in 22 years this will be the 3rd attempt to nuke them. Thanks Erik. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> One possible reason that things aren't going according to plan is that there never was a plan in the first place. ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
