[TriEmbed] Need help with a beginner circuit design

[Brian]

Hi Dave,

Let me echo what others have said, this is a fine forum for your 
inquiry.  So: Where is your high voltage coming from?  Are you planning 
to generate it from the same battery that is powering the rest of the 
circuit?

I'm not sure the MAX1771 is going to meet your needs, if you're looking 
for 80VDC.  I'd suggest instead another 555 astable vibrator driving the 
8-ohm side of a 8/1000-ohm audio matching transformer.  There's some 
Ohm's Law and transformer math to be done to get just the voltage you 
want, but the basic idea is the 555 chops your battery voltage (9v?), 
then the matching transformer steps it up.  On the output side, you'd 
outfit a rectifier and some tank capacitors to smooth it back out to DC.

Some important considerations:

How steady do you need your HV to be?  Can you tolerate some ripple?

How important is the actual HV potential?  Is 80VDC an important target 
or could it be higher than that?

As the HV is switched on/off, can your application handle it ramping 
rather than switching?

As an aside, out of a sense of due diligence, does your design include 
appropriate measures to keep the HV out of reach?

-B

On 10/27/2015 6:55 PM, Dave Buster via TriEmbed wrote:
> Hi-
> I'm a long-time lurker on this email, but I'm not active.
>
> It's been many, many years since I did Industrial engineering at NC
> State, and I've mostly been doing data communications and cyber security
> since then. In other words.... I'm no longer hands on. I don't even know
> how to solder any more.
>
> sigh.  This is embarrassing..
>
> Now I have a need to design a build a simple analog circuit for a hobby
> of mine, and I'm getting stumped.  I'm wondering if someone has some
> time to give me a few pointers and/or help me with the design.
>
> The battery-powered circuit will be very simple.  I need to flash an LED
> a couple of times per second (I got that working with a 555 timer), then
> I need to send beeps to a little piezo speaker (I'm still working on
> that), and finally, I need to pulse a high-voltage/low-current DC signal
> about twice per second.  I'm thinking of using a max1771 DC-DC converter
> for that.  ...and I'm in over my head.
>
> I won't be able to make it to the November meeting, but would it be
> possible to get someone to spare an hour some other evening to discuss this?
>
> Anyone want to volunteer to help a life-long learner?
>
> Here is an email account I don't use very much, but I'll be checking it:
>
> dave at tritonsharksignal.com <mailto:dave at tritonsharksignal.com>
>
> Also, if this is not appropriate for this email thread, my apologies.
>
> thanks!
>
>
>
> --
> Dave Buster
>
> KK4ELT on 2 meters
> Never look at the trombones, it only encourages them.
> *Ri
> <http://t.sidekickopen23.com/e1t/c/5/f18dQhb0S7lC8dDMPbW2n0x6l2B9nMJW7t5XX45vMtjYVQZgwH64R1y4W8r4TLx56dPn8f5RTxgR02?t=http%3A%2F%2Fwww.brainyquote.com%2Fquotes%2Fauthors%2Fr%2Frichard_wagner.html&si=4964982235594752&pi=6f98b148-9f74-482e-d75c-f87f6847e43c>chard
> Strauss*
>
>
>
>
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