Re: Transistor booster design

On Aug 2, 1:02 pm, John Devereux <jdREM...@xxxxxxxxxxxxxxxxxx> wrote:
linnix <m...@xxxxxxxxxxxxxxxxxx> writes:
On Aug 2, 11:58 am, John Devereux <jdREM...@xxxxxxxxxxxxxxxxxx> wrote:
John Larkin <jjlar...@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx> writes:
John Larkin wrote:

On Sun, 29 Jul 2007 12:15:53 -0700, linnix <m...@xxxxxxxxxxxxxxxxxx>
wrote:

I can't find the old thread. But here is the two transistors booster
model and schematic, as promised.

For BC847B, 6V to 15V @ 1ma:

http://linnix.com/power/main.php?vcc=6&coil=330&load=15

Blocking oscillator boost converter:

http://s2.supload.com/free/BlockOsc.jpg/view/

So draw us a boost converter that has no current spikes.

I liked your tinylogic circuit - but I think linnix wants to do it
just with discrete semis and an inductor. I suppose transistors are
*very* cheap.

Main problem is building the additional CMOS Schmitt trigger cell.
Transistors are cheap, but additional processes are expensive.

It's part of a chip? I had not realised that! I don't know anything
about chip design, but I would think you need to be even more careful
to avoid e.g. latchup.

It will be regulated and enabled by a micro. If the micro does not
see oscillations (rising output), it can toggle the common emitter
junction. This by itself should create enough impulses to start it.
It only requires 15V for 30 to 60 seconds, then off for a few minutes.

So far, it does not seem to have problem starting by itself. The
problem is drawing more than 4mA from the batteries.

Are your passive parts external?

Yes, hard to put big L & C inside.


I wonder is there a better 2-transistor circuit?

I'm still wondering...

--

John Devereux


.

Relevant Pages

  • Re: Transistor booster design
    ... just with discrete semis and an inductor. ... Transistors are cheap, ... about chip design, but I would think you need to be even more careful ...
    (sci.electronics.design)
  • Re: Transistor booster design
    ... Transistors are cheap, ... about chip design, but I would think you need to be even more careful ... It will be regulated and enabled by a micro. ...
    (sci.electronics.design)
  • Re: Transistor booster design
    ... I liked your tinylogic circuit - but I think linnix wants to do it ... Transistors are cheap, ... about chip design, but I would think you need to be even more careful ...
    (sci.electronics.design)
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