1. I have to control a 3W single led intensity, need to vary intensity linearly from 0 to 100% as user rotates potentioneter of 10K.

2. is there any dedicated low cost asic solution available for this, which can do this.

3. Most of i have checked need a PWM signal to ic like here
http://www.ti.com/power-management/led-driver/led-lighting/products.html#p207=DC Linear;DC/DC&p2297=Analog

I am looking for some solution where a potentiometer can do the dimming directly, instead of connecting additional ckt for asic


4. Voltage of Li-Ion cell: 3 to 4.2V
if charging, then voltage go to 5V from main adapter

So input voltage for IC go from 3V to 4.2V

 

hi VT,
Using a 10k pot for driving a 3W LED from 4V, it will not be feasible.
E

 

Hello,

What are the specs of the led and battery?
How are you charging the battery?
A to high voltage on a LI battery may cause fire.

Bertus