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Hubert Tchio said:thank you for your response, but i believe adding a 10K in the circuit also increase power loss thereby reducing the overall efficiency of my design (correct me if I am wrong).
As I understand it, you intend to use the LED current and LED forward voltage to identify the LED die temperature.Hubert Tchio; in .pdf said:Secondly, I indeed to add a temperature measurement as an additional input but I don’t know how to do this. What I mean is to put another current monitor to measure the LED current and use it as feedback to the temperature measurement. I don’t intern to use a temperature sensor.
Can anyone be of help?
No.A model of the LED you are using looks like a voltage step in series with a resistor having a value of about 0.416 ohms.Hubert Tchio said:Are you saying my actual schematic is enough? should I just change the series Resitor to 0.416 ohms and the work is done?
Baluncore said:To limit junction temperature to 125°C requires the environment remain below about 105°C.
By independently monitoring LED heatsink or substrate temperature, you can reduce the duty cycle, the LED current and so LED power dissipation as the environmental temperature approaches the limit of 105°C. If the change begins only at 95°C and takes place so that current falls linearly to zero at 105°C, then the LED will be over-temperature protected. That might be achieved by reducing the current reference voltage at high temperatures.Hubert Tchio said:Do you think there is any other way to implement LED die temperature on the model of the LED i am using?
The area parameter of "14" at the end of the Q6 and Q1 lines is wrong. That 14 is from a different ratio parameter specified in the data sheet.Hubert Tchio said:Q6 R N001 v+ 0 pnp1 14
Q1 N003 N003 R 0 npn1 14