I'm having trouble interpreting the thermal characteristics of the Microchip CL2N3-G Constant Current LED Driver chip.
Here's the datasheet: CL2N3-G Constant Current LED Driver 1
What I want to do is to power a single LED from a 60 VDC power source.
I'm planning on using the TO-92 package.
The problem I'm encountering is when I calculate the temperature rise of the CL2N3-G.
The spec states for the TO-92 package a thermal resistance of 132°C/W.
Here's the equations I'm using:
60 V - 2.1 V (LED Vf) * 20 mA = 1.152 W 1.152 W * 132 (Thermal Resistance) = 158.8°C
This seems like a ridiculously high temperature just to power a single LED. Is this correct or am I missing something?
Thanks for your assistance and insights.