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  1. I

    Theory discussion moved from Q/A

    Try measuring the current gain of a few hundred 2N3055 transistors to find one with a gain that's at it's specifications min level!!! I'm sure "gain variation" follows a standard distribution and components with spec's out beyond 6 sigma are hard to find!! I agree with you from a analytical...
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    Led display Digital Voltmeter question

    From a purely analytical standpoint, "the theory expert" does make SOME valid points!! From a practical, "I only have to build one of these, not 10,000...", it probably doesn't matter!!
  3. I

    Capacitor Voltage

    equivalent series resistance and  equivalent series inductance
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    how to design very small 6V power supply @100mA

    Here's probably more than you want to know about it... it shows a split primary winding of 13-13. This is because the program can't do half turns. TRANSFORMER PERFORMANCE SUMMARY Design Name: Designer: Date/Time:    06/30/06 09:45:45 Project:  Untitled Notes: TRANSFORMER DESCRIPTION Core...
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    how to design very small 6V power supply @100mA

    The transformer design isn't that bad... 25 turns primary and 5 turns secondary. For a SMPS, I think you could get away with a Feroxcube ER14.5 core with 3F3 material (inductance factor of 1400nH +/-25%) running at 400KHz on a single ended forward converter. It would have an ~ duty cycle of...
  6. I

    LM317 high voltage

    If you look at the LM317HV spec, you will see that the max input to output voltage is 60V. That does not mean 60V is it!!! You could have 120VDC in and 100V out which is fine because you haven't violated the 60V max differential.
  7. I

    Tssop package -> DIP

    One guy here where I work does some "moonlighting" and has used, with some success, a small toaster oven to reflow solder paste on SMT PCB's. The only trick is to find the right temperature profile.
  8. I

    L298n IC socket, urgent!!!

    The "multiwatt15" package isn't really meant to go in a socket.
  9. I

    Newb Question: 12v-80ma transistor switch

    Use caution when talking about positive and negative voltages in regards to transistor biasing... use "potentials" so that it applies in all cases. see:        http://www.electronics-lab.com/forum/index.php?topic=7097.msg43806;topicseen#msg43806
  10. I

    can any one explain zener breakdown using energy band diagrams?

    Avalanche breakdown occurs in all diodes!!! It's just a question of how well the breakdown voltage level is controlled (through doping levels). Reverse bias any "plain Jane" diode and it will work just like a zener, reverse the polarity across a zener, and it will behave just like a diode. The...
  11. I

    DRC and net list

    Yes I did, and yes it is!!!! Those that know, know and those that don't, don't!!! The package is PADS (more than adaquate)... I don't do the layout's, the CAD designers do it with my guidance... I'm a circuit designer, not a PCB designer. Just in case.... I'm NOT talking about the auto-routers...
  12. I

    Electromagnetic field interference.

    This is not "my diagram".... The point I was/am trying to make is that shielding doesn't necessarily have to tie to "ground" or a "common point" of a circuit all the time, and sometimes, the shield is more effective if tied elsewhere, this is a irrefutable fact. The notion that all shields...
  13. I

    DRC and net list

    I don't want to insult anybody
  14. I

    Electromagnetic field interference.

    The "common reference" can be anything I want it to be, it DOES NOT have to be something called ground or zero... just a "common point". In this circuit for example, you could take the +5 from back wheel battery, connect the +9 and the 5V return from the blade motor and call this my reference...
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    DRC and net list

    Yes, but your talking digital. Digital is a different story... yes, it'll work there. I was talking power analog design. Do you mean this software!!! http://www.cheap-software-megastore.com/index.php?target=desc&progid=1329
  16. I

    gating signal for six MOSFETS or SCRS

    I think the more interesting question is how to phase shift each of the gate pulses 120 degrees for each phase!!
  17. I

    Electromagnetic field interference.

    Like I said... EMI and EMC are both a little bit of "black magic".
  18. I

    Electromagnetic field interference.

    EMI and EMC are both a little bit of "black magic".  Why would you say that their ground wires have to be connected together?? What they need is a common reference and that reference doesn't have to be ground. In fact, sometimes it's to your advantage to not have ground at the reference.... it...
  19. I

    DRC and net list

    I've been designing DC-DC converters for the past 15 years (but I do go back to the days of tape and doughnuts).... if ANY of our CAD designers tried to auto-route one, then they would be looking for work!! Yeah..... I suppose it's industry dependent, and that there are low frequency, low power...
  20. I

    Analog To Digital Converter

    One of the inputs to ammeter is connected to "ground". That means you can only measure ground referenced signals, unless of course, the whole thing is floating.
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