- #1
kresyzig
- 6
- 0
Delay Circuit with "Logical-Quality" Output?
Hi,
First of all, hello everyone (my first post here)!
I need to make a delay circuit for my car, but I need the transition time of the output voltage to be quick, because I will use the voltage to activate a power MOSFET transitor, which will in turn activate light ballasts, whose maximum current draw is at startup. I need a ~10 seconds delay, so using a simple RC circuit won't do it (because dV/dt would drop with time). I doubt that using a current barrier will do it either, because dV/dt in this case is approximately constant.
So what I need is a delay circuit whose output voltage stays very low for almost the whole delay time, then goes up quickly to activate the power MOSFET transistor. Is that something possible with an analog circuit? Otherwise, what kind of programmable chip could I use? In fact, I need a couple of delay circuits (with different time constants), I will need to activate 3 of these power MOSFET transistors and I will also have about 1/2 dozen inputs to my circuit (from different car signals). I wanted to go initially with an analog circuit, but space constraints and flexibility now make me lean towards a programmable digital circuit...
Thanks!
Hi,
First of all, hello everyone (my first post here)!
I need to make a delay circuit for my car, but I need the transition time of the output voltage to be quick, because I will use the voltage to activate a power MOSFET transitor, which will in turn activate light ballasts, whose maximum current draw is at startup. I need a ~10 seconds delay, so using a simple RC circuit won't do it (because dV/dt would drop with time). I doubt that using a current barrier will do it either, because dV/dt in this case is approximately constant.
So what I need is a delay circuit whose output voltage stays very low for almost the whole delay time, then goes up quickly to activate the power MOSFET transistor. Is that something possible with an analog circuit? Otherwise, what kind of programmable chip could I use? In fact, I need a couple of delay circuits (with different time constants), I will need to activate 3 of these power MOSFET transistors and I will also have about 1/2 dozen inputs to my circuit (from different car signals). I wanted to go initially with an analog circuit, but space constraints and flexibility now make me lean towards a programmable digital circuit...
Thanks!