Re: dc/dc converter 12/200V

On Sat, 16 Apr 2005 22:06:05 +0200, "Jan Heijkamp" <setje@xxxxxxxxxxx>
wrote:

>Hi Jim,
>
>I have take a second look at the schematic but i don't see how it works.
>The only thing i can think of is that because the turning off Q1 if the
>current is 5A trough L1 there a induction counter to the current is being
>created.
>That energie goes in C1 until Q1 is turning on and is pulling that energie
>trough the ignition coil.
>If this is not the case, can you explain in short how it works?
>btw. Sorry for my bad english. I op you understand what i try to say.
>
>Jan
>
>
[snip]

Turning ON the transistor does two things... dumps the capacitor
through the ignition coil primary (firing the plug) and begins
charging L1.

When the L1 current reaches 5A a control circuit (not shown) turns off
the transistor, which dumps the L1 energy into the capacitor.

Next point opening, or star wheel control signal, turns on the
transistor, repeating the cycle.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.
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