I'm trying to build a circuit to control accent lightning made up for multiple LED strips. The total draw of all the LEDs would be approaching 5 amps @ 12v, and I'd like to control them all from the same point, and just wire the LEDs in parallel.
The behaviour I'm trying to achieve is to have the LEDs stay on all the time at a low brightness (~20% duty), then when a signal from a motion sensor comes in, turn the brightness to maximum.
I think this could be done with a high current transistor being driven by a 555 set to 20% duty and a trigger from the motion sensor tied to the transistor also. And that would be simplest. But I'm also trying to get the effect of fading on/off. When the LEDs transition from 20% to 100% duty cycle, I'd like to make it a smooth, rather than an abrupt increase in brightness.
What kind of circuit would be able to accomplish this elegantly?
The behaviour I'm trying to achieve is to have the LEDs stay on all the time at a low brightness (~20% duty), then when a signal from a motion sensor comes in, turn the brightness to maximum.
I think this could be done with a high current transistor being driven by a 555 set to 20% duty and a trigger from the motion sensor tied to the transistor also. And that would be simplest. But I'm also trying to get the effect of fading on/off. When the LEDs transition from 20% to 100% duty cycle, I'd like to make it a smooth, rather than an abrupt increase in brightness.
What kind of circuit would be able to accomplish this elegantly?