PCB Thermal Relief Calculator

Formula

The formula to calculate the PCB Thermal Relief Width (TW) is:

\[ TW = \left( \frac{X \cdot 0.60}{Y} \right) \]

Where:

\(TW\) is the PCB Thermal Relief Width (trace width)
\(X\) is the overall length of the SMT Pad
\(Y\) is the quantity of thermal connecting traces

What is PCB Thermal Relief Width?

PCB Thermal Relief Width refers to the width of the thermal relief traces on a printed circuit board (PCB). These traces help in managing the heat dissipation from surface-mounted devices (SMDs) by providing a controlled path for heat to flow away from the component. Proper calculation of thermal relief width is crucial for maintaining the thermal integrity and reliability of the PCB.

Example Calculation

Let's assume the following values:

Overall Length of SMT Pad (X) = 10 mm
Quantity of Thermal Connecting Traces (Y) = 4

Using the formula to calculate the PCB Thermal Relief Width:

\[ TW = \left( \frac{10 \cdot 0.60}{4} \right) = \left( \frac{6}{4} \right) = 1.5 \text{ mm} \]

The PCB Thermal Relief Width is 1.5 mm.