12V delay circuit
So I have a pretty simple problem I know I can solve, but wanted to put this out there to see if I was going about it the simplest way.
I picked up a Webmaster power on module years ago while he was still making them knowing I'd get my carpc moving some day. Now I've found a minor hiccup.
The laptop itself doesn't have a hard power button. I cracked open the case and it's a soft button on the keyboard's circuit board, so nothing to solder to.
I am using a docking station that does have a hard power button with solder contacts, so I'm in business. I can use the manual power button from the Webmaster module to turn the computer on and off so I know that's installed correctly.
The issue is that the laptop DC-DC power supply I have is connected to the ignition on circuit, and the docking station has to have power to it in order for that hard power button to do anything. The Webmaster module is sending the power pulse before the docking station is able to turn on the computer. I just need a simple delay, say two seconds roughly, for the docking station to be ready to go.
So I just want to wire it in line before the Webmaster module so it sees the 12V trigger with the delay and it's action on the power button circuit remains the same.
This is my current option I'm looking at after a quick search.
Seems simple enough and is adjustable to ensure it's just right. My concern is that it's more complicated than I really need. $30 isn't a big deal, but if there is a smarter choice you can point me towards I'll take a look.
Could just use one of these, http://www.amazon.com/DEI-528T-Pulse.../dp/B0009IR4AC
Programable from 1-90 sec delay.
PhilG beat me to it.
I usually suggest DIY circuits feeding plain relays, but for the price (and features!), even I intend getting a few DEI 528Ts for my own odd ad-hoc applications or trials (unless I get my "universal" PIC 08M2 PCB up & running first).
The 528T is often used & recommended on the12volt.com. I have never seen any reliability issues etc.
PS - only $9.99 from SgtDAT216 as linked from PhilG's link (only 1 left).
There's a handy diagram here, and I've only seen the 2-page manual - eg the12volt (still the common 2005 version).
Thanks guys. I figured there was a cheaper option to achieve the same goal.
Originally Posted by OldSpark
Ordered, thanks guys.
That 9.99 price on amazon was without shipping, I went with the more reliable seller that was 16.99 with free shipping. The difference was less than two dollars for a reputable company.