I need help with pulse width modulator with constant 12volt output

[ron roberts]

I need help with pulse width modulator with constant 12volt output

Hi all hope some one can help with this.
I need to build a circuit that will allow a constant 12volt until it’s activated, when it’s activated it needs to pulse the output just like a pulse width modulator, when switch off it must go back to a constant 12volt until it’s activated again.

The output needs to supply a +12volt rail to drive an array of bulbs.

I’ve tried to show you what I’m looking for in a diagram hope it helps.

**broken link removed**

 

[audioguru]

You fogot to tell us what kind of light bulbs you have. Most people use LEDs today.
You also forgot to tell us how the "12V DC PSU" steps up the voltage from 5V to 12V.

You have two control boards so we don't know which one steps up the voltage.

 

[ronv]

So to understand. You would like the bulbs to be on full utill some signal (Green wire from control board) tells it to go into dimmer mode (PWM)? Does the green wire also tell it how bright you want the bulbs or is there another adjustment for that? If the green wire tells it how bright-- what voltage = what brightness.
Need to know how much current for each bulb or all of them. Is it correct to say the control board supplies ground to the bulbs?