does anyone have a shutdown controller design they can share?

**djrkd** · 12-28-2003, 12:02 PM

I want to build my own shutdown controller, does anyone have any schematics for one?

**MikeH** · 12-28-2003, 05:30 PM

Check out page 14 of this

**mst** · 12-28-2003, 05:53 PM

Thank you very much for your link,it is a MUST read for all with Epia Mini-Itw motherboards

Originally Posted by MikeH

Check out page 14 of this

**djrkd** · 01-01-2004, 02:07 PM

is that just a shutdown controller? or also a tank circuit?

**MikeH** · 01-01-2004, 02:20 PM

DJ

is that just a shutdown controller? or also a tank circuit?

Are you referring to the ITPS? It is a turn-on/shoutdown controller plus a (somewhat unusable) 12V regulator. As I understand, a "tank circuit" usually consists of a diode feeding a large capacitor, which attempts to hold enough charge to continue feeding 12v to you carpc during engine cranking. The ITPS DOES NOT do this. However, they have recommended the following as a way to help overcome the crank issue. This approach should work much better than a capacitor:

**Ricky327** · 01-01-2004, 08:39 PM

MikeH,

Some has already tried this solution, and surprised the ITPS barely work. This is due to the fact that the ITPS already need 13.3V atleast to output a regulated 12V, loosing another 0.6V throught the diode make the matter worst.

The battery symbol is drawn funny

**djrkd** · 01-04-2004, 02:49 PM

i just want a design simmilar to jeffs...

**MikeH** · 01-05-2004, 04:24 PM

Ricky

Some has already tried this solution, and surprised the ITPS barely work. This is due to the fact that the ITPS already need 13.3V atleast to output a regulated 12V, loosing another 0.6V throught the diode make the matter worst

Agreed, but I have bypassed the onboard 12v regulator. I'm using the laptop (Radio Shack) regulator before going into the ITPS. Therefore, there should only be a .1v drop across the switching FET on the ITPS. If my backup battery is fully charged, I should be able to get 11.3v+ or so (marginal, but should keep the mobo from rebooting) at the output of the ITPS during cranking. Obviously, I haven't tried it yet, so I'll let you know how it works when I do.

The battery symbol is drawn funny

Yeah, looks funny to me too. It should have more cells...looks like an asymmetrical capacitor.

**djrkd** · 01-12-2004, 05:10 PM

all i wanna do is build a fairly simple shutdown controller.

**moahdib** · 01-14-2004, 05:01 AM

Check out my "old" mp3car project page. In the hardware section you should see Jeff's shutdown controller (original) which I built a first working prototype of and its schematic.

http://home.comcast.net/~danielsoh/shutdown.htm