but if i turn off from + wire, how can i have fade off
couse i want, when i turn on to have fade on, and when i turn off to have fade of

or c1 hold that power

 

Hadn't thought about that. You are going to flash slowly,why not turn it off when it is dark?

It can be done, but it's going to take almost as much circuitry as you've already got.

Are you sure you want to go this route?

 

ahh i was thoudth this is fade on fade off
this is yest fade on
what should i do, couse i need that :/

 

Why? You are talking about turning the circuit on and off, which has nothing to do with fade on and fade off. I suspect you have a different vision that what I thought you were talking about here.

With power the circuit will indeed fade on / fade off, continously. If you turn the power off it will go out like a light bulb.

This can be done, but it will not be the power switch that does it. It will be another control, start and stop if you will. Power switches disconnect the circuit from power source, nothing more.

It will likely be another 555 and a transistor, along with a handful of resistors and capacitors.

 

here is what i want
turn on, from 0% to be 100% light for couple of seconds/minutes, and to stay on 100% untill i turn off, when i turn of from 100% to 0% light to be in couple of seconds/minutes

and with video
http://www.youtube.com/watch?v=DW2rFEZZJRs

 

OK, that is not a fader. A fader pulses, on / off / on / off etc...

You want a soft start and soft off, which is totally different. PWM for extended duration may still be the best way to go, given the length of time you want it to happen, and the currents you are using. With 12VDC and 20 LEDs you are going to pull around 1A. 4 LEDs take a lot less circuitry.

Seconds is easy, minutes is a very long time however. The simple transistor arrangement shown in the video's is not quite duplicated in 12.3, but very close.

You want a simple arrangement to experiment with, or a more complex arrangement to drive all 20 LEDs up front. I will probably end up drawing both.

I've been in an all day function for DeMolay, and will be again tomorrow.

 

i was thinking thats is fade on/off, yest i want soft start for as much longer time as posible

thanks a lot

 

Sorry about the confusion, most of your work is not wasted however. I am currently thinking SPDT toggle switch, or a push button. How do you want it?

I couldn't sleep, so came to grab the current schematic off the board.

 

Here is a revised schematic, I think it will do what you want it to do...

I will draw simpler versions that are more similar to what you saw. They won't work for your application, as at a minimum your LEDs total current is 1 amp, but I think you might like to see them to play with them and understand how they work.

R22 is not needed unless the circuit doesn't quite turn the LEDs fully off (TS = Test Select). The way resistor tolerances work this could be a problem. If you do need it use either a 47Ω or a 100Ω, depending how bad the problem is. As designed this circuit will go between 1 seconds and 100 seconds. If you want more time just use a larger resistor for R24. A 1MΩ variable, for example, will give you up to 1000 seconds (16.7 minutes).

I think you will be happy with this design, it will run very, very cool (as in temperature). I'm going to use your last PCB design unless you object. You want your name on it? If so, how do you want your name portrayed on the print?

Sorry about the misunderstanding.

 

great will use the largest variable resistor what can find (will be happy with 5-6min)
will make the pcb and post here to see it


on attachent are pdf with the layout and the .pcb file made with PCB wizard
no need for credits, you help me a lot here

thanks a lot again, great help

 

the schematic its done i got the components here, will upload later when i get that laptop

now i got one question, how to make turn on/off

the timer i use its on 220V, then i convert the power to 12V

any suggestion?

 

Since it takes power to fad out slowly, you probably want the 12VDC to stay on permanently. Use the AC to power a relay, which will power a switch.