I have a circuit that will PWM a triac for phase control of a motor. I am really confused on how to size the heat sink for the operation of the circuit.
I have measured the voltage drop across the Triac and used the current to find the "ON" resistance but I want to be able to calculate it. I used the knee voltage chart but not sure I am calculating it correctly. My Case to Junction temp with my selected heat sink is about 140°C. My heat sink's thermal resistance is 15°C/W.
Due to size and cost I need to be able to accurately calculate the required heatsink. Once I find the power dissipated, calculating the heatsink is not a problem.
The current will be 13A and the voltage supplied to the motor 115V@50Hz.
The triac is a little fuse Q6016LH3 (Isolated Tab TO-220). http://www.littelfuse.com/~/media/e..._thyristor_qxx15xx_qxx16xhx_datasheet.pdf.pdf
Here is the circuit.
Any suggestion on calculating the heat dissipation or ways to improve the circuit would be appreciated.
David
I have measured the voltage drop across the Triac and used the current to find the "ON" resistance but I want to be able to calculate it. I used the knee voltage chart but not sure I am calculating it correctly. My Case to Junction temp with my selected heat sink is about 140°C. My heat sink's thermal resistance is 15°C/W.
Due to size and cost I need to be able to accurately calculate the required heatsink. Once I find the power dissipated, calculating the heatsink is not a problem.
The current will be 13A and the voltage supplied to the motor 115V@50Hz.
The triac is a little fuse Q6016LH3 (Isolated Tab TO-220). http://www.littelfuse.com/~/media/e..._thyristor_qxx15xx_qxx16xhx_datasheet.pdf.pdf
Here is the circuit.
Any suggestion on calculating the heat dissipation or ways to improve the circuit would be appreciated.
David