Hi all,
Please find the attached schematic.
I have 5x2 led configuration.
The Vf of LEDs are 1.9V-2.4V at 20mA.
I want to drive it by 12V@30mA.
I have a dedicated constant current led driver STP16CPC05 which shink the current up to 100mA.
I have set the resistance value such a manner it shinks current only 30mA.
Now u can see total cureent is 30mA. Current divided in both branches is 16mA and 14mA.
So I want to know that why current is equally not devided in both branches.
I have 10 phodetector to detect the signal and connected alngwith LED.
So my questions are now.
1. Why current in parallel branches are not same.
2. How do we calculate photocurrent of LEDs.
3. Does 2mA difference really makes sense.
4. How to determine the output of photodetector.
What if the led glow the intensity of 16mA and what if the led glow with 14mA.
5. How much impact on detector output.
Please consider a idle condition ignoring distance , mounting angle etc.
Please do explain as per my doubts.
Please find the attached schematic.
I have 5x2 led configuration.
The Vf of LEDs are 1.9V-2.4V at 20mA.
I want to drive it by 12V@30mA.
I have a dedicated constant current led driver STP16CPC05 which shink the current up to 100mA.
I have set the resistance value such a manner it shinks current only 30mA.
Now u can see total cureent is 30mA. Current divided in both branches is 16mA and 14mA.
So I want to know that why current is equally not devided in both branches.
I have 10 phodetector to detect the signal and connected alngwith LED.
So my questions are now.
1. Why current in parallel branches are not same.
2. How do we calculate photocurrent of LEDs.
3. Does 2mA difference really makes sense.
4. How to determine the output of photodetector.
What if the led glow the intensity of 16mA and what if the led glow with 14mA.
5. How much impact on detector output.
Please consider a idle condition ignoring distance , mounting angle etc.
Please do explain as per my doubts.
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