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The components I have are timer 555 chip, capacitors, and transitors. I want to create sleep functionality for a led lamp which consists of 6 leds in parallel and pnp, npn transistors.
I want this circuit to sleep of time interval of 10 minutes. I just want some recommendations because I have no idea where to start
In your circuit you have posted, remove R7, replace it with a 680uF capacitor. And then, connect the base of that transistor to the ground/emitter using a 1Megaohm resistor.
This way transistor will get the base drive through the cap for about 10 minutes until it is fully charged by the 1 megaohm resistor. This mod is the easiest one to accomplish your objective. Of course more can be done to reset the timing cycle etc by adding more components.
555 is not really needed unless you want to have more precise control of the timing.
We must assume that by "sleep functionality" you mean that the LEDs will turn off after some time period after being powered?
The simplest way to do this would be to use a resistor/capacitor time-constant to remove the base drive current to the transistor after the desired time period.
