A transistor with a height of 0.4 cm and a diameter of 0.6 cm is mounted on a circuit board. T

step 1 So here in this question the surface area of transistor is given by A is equals to pi 0 .6 centi

A transistor with a height of 0.4 cm and a diameter of 0.6...

A transistor with a height of $0.4 \mathrm{~cm}$ and a diameter of $0.6 \mathrm{~cm}$ is mounted on a circuit board. The transistor is cooled by air flowing over it with an average heat transfer coefficient of $30 \mathrm{~W} / \mathrm{m}^{2}$. $\mathrm{K}$. If the air temperature is $55^{\circ} \mathrm{C}$ and the transistor case temperature is not to exceed $70^{\circ} \mathrm{C}$, determine the amount of power this transistor can dissipate safely. Disregard any heat transfer from the transistor base.

Key Concepts

Convective Heat Transfer

This concept deals with the transfer of heat between a surface and a moving fluid (such as air). It is characterized by the heat transfer coefficient, which quantifies the rate at which heat is removed from or added to a surface per unit area per unit temperature difference. In electronics, controlling convective heat transfer helps ensure that components like transistors remain within safe operating temperatures.

Newton's Law of Cooling

Newton's Law of Cooling provides the foundation for quantifying convective heat transfer. It states that the rate of heat transfer from a surface is proportional to the temperature difference between the surface and the ambient fluid, multiplied by the surface area and the convection coefficient. This relationship, expressed as Q = hA?T, is essential in calculating how much power a component can safely dissipate without exceeding a specified temperature.

Surface Area Calculation for Convection

In the context of heat dissipation, accurately determining the exposed surface area of a component is critical because the area directly influences the total heat transfer rate. For components with simple geometries, the surface area can be calculated using standard geometric formulas. Understanding how to compute and use the surface area in the convection equation is key to predicting temperature rises and ensuring thermal safety.

Thermal Management in Electronic Systems

Thermal management involves the design and implementation of strategies to control the temperature of electronic components to prevent overheating and ensure reliability. It includes the application of principles such as convective heat transfer and surface area considerations to dissipate excess heat effectively. Proper thermal management is crucial to maintaining performance and preventing damage in electronic circuits.

Transcript

Please give Ace some feedback