[Prev][Next][Index][Thread]

Re: NE555 driven coil WAS:Re: SCR driver coil...






>Date: Fri, 05 Feb 1999 21:37:18 -0700
>To: tesla-at-pupman-dot-com
>Subject: NE555 driven coil WAS:Re: SCR driver coil...
>From: Tesla List <tesla-at-pupman-dot-com>
>
>Original Poster: Paolo <pagaiard-at-geocities-dot-com> 
>
>
>
>
> 
>  "Hi all,
>  I have to realize (for an electronics exam) a solid state driven TC
>  with a very high efficiency.
>  I need to know your opinion on a couple of ideas.
>  Suppose I build a ne555 based impulse generator which
>  makes 1 us long pulses with a (say) 100-500Khz repetition rate."
  
   The 555 falls apart when you try to use it for fast narrow pulses.
At least the bipolar version does, the newer Cmos variety is faster
but I don't know by how much. Check the spec on this stuff before
you frustrate yourself with parts that are far from the "ideal"
spice fantasy world.  For fast rise/fall and simplicity, make an
LC oscillator from a schmidt trigger cmos gate like 4093(?) running
at 12 to 15 volts. (you do the research to discover why this is better).

   
>  

Then I send those pulses into a power transistor (a BJT working a
>  current controlled switch, of course)
>  via a 2N2222 based current buffer (say a follower emitter).

Not sure what you mean here. ccs=scr ???? How about an IGbjt?
 
>  I could drive directly an inductor tightly coupled to a tesla
>secondary
>  winding but with the power available (30W or so) I suppose the yeld
>  would be quite low.
> 
>  But what if I feed a LC circuit with those current pulses?
>  The LC must be tuned and coupled to the secondary winding, and 
feeding
>  it with 1 us pulses, maybe with a repetition rate tuned to the TC
>frequency
>  should create into the LC couple powerful oscillations
>    and thus make for a high power yeld into the secondary winding.
>
  Bet you can't even get spice to make that work! Try it, we can't
do all your homework for you.
 -Jim McVey
>  
>
>
>


______________________________________________________
Get Your Private, Free Email at http://www.hotmail-dot-com