led control with microcontroller

[otuzsubat]

hi, i have to design a circuit which will control 114 leds. these leds must have different 4 current steps to change brightness. 4 current level is 5ma, 10ma, 15ma and 20 ma.

design rules are below
1. 4 current level are 5ma,10ma,15ma,20ma.
2. each led can be turned on/off individualy.
3. when i turned on some leds, they must have same brightness level. for example when i turned on 20 leds, each led must be driven by 5 ma.

what is the simplest method to do this?

 

[barry]

Simplest method: Hire me (or somebody else on this board) to do your work for you. This is not very cost-effective, nor will you learn anything, but it is the simplest method and will require the least amount of effort on your part. If that's not what you had in mind, you could, perhaps, make an attempt at this, and then come back here with a post asking specific questions about your attempt, problems you are having, etc.

 

[issaiass]

I recommend you to divide your project in steps.
1 - Divide the 114 leds, i.e. in 6 groups of 19 leds
2 - make a controller board for the leds, this board must have 3 ports (8 + 8 + 3) of your microcontroller dedicated to activate the leds and a port pin for multiplex in time these 19 leds
3 - If you have 6 boards, you have to multiplex in time, 360Hz (60 * 6)
4 - For mA reduction or increase, use PWM for intensity.

Hope this tip helps