As more and more components are placed on a single...

As more and more components are placed on a single integrated circuit (chip), the amount of heat that is dissipated continues to increase. However, this increase is limited by the maximum allowable chip operating temperature, which is approximately $75^{\circ} \mathrm{C}$. To maximize heat dissipation, it is proposed that a $4 \times 4$ array of copper pin fins be metallurgically joined to the cuter surface of a square chip that is $12.7 \mathrm{~mm}$ on a side. (a) Sketch the equivalent thermal circuit for the pinchip-board assembly, assuming one-dimensional, steady-state conditions and negligible contact resistance between the pins and the chip. In variable form, label appropriate resistances, temperatures, and heit rates. (b) For the conditions prescribed in Problem 3.27. what is the maximum rate at which heat can be dissipated in the chip when the pins are in place? That is, what is the value of $q_{c}$ for $T_{\epsilon}=75^{\circ} \mathrm{C}$ ? The pin diameter and length are $D_{p}=1.5 \mathrm{~mm}$ and $L_{\gamma}=15 \mathrm{~mm}$.

As more and more components are placed on a single integrated circuit (chip), the amount of heat that is dissipated continues to increase. However, this increase is limited by the maximum allowable chip operating temperature, which is approximately $75^{\circ} \mathrm{C}$. To maximize heat dissipation, it is proposed that a $4 \times 4$ array of copper pin fins be metallurgically joined to the cuter surface of a square chip that is $12.7 \mathrm{~mm}$ on a side. (a) Sketch the equivalent thermal circuit for the pinchip-board assembly, assuming one-dimensional, steady-state conditions and negligible contact resistance between the pins and the chip. In variable form, label appropriate resistances, temperatures, and heit rates.
(b) For the conditions prescribed in Problem 3.27. what is the maximum rate at which heat can be dissipated in the chip when the pins are in place? That is, what is the value of $q_{c}$ for $T_{\epsilon}=75^{\circ} \mathrm{C}$ ? The pin diameter and length are $D_{p}=1.5 \mathrm{~mm}$ and $L_{\gamma}=15 \mathrm{~mm}$.

Key Concepts

Equivalent Thermal Circuit

This concept involves modeling the physical heat transfer system using an analogy to electrical circuits, where temperatures are analogous to voltages, heat flow rates to currents, and thermal resistances to electrical resistances. It simplifies complex thermal interactions into a network of resistances and nodes, making it easier to analyze temperature drops and heat dissipation paths in multi-component systems.

Thermal Resistance

Thermal resistance quantifies the opposition to heat flow through a material or a system, similar to how electrical resistance limits current flow in an electrical circuit. It is a key parameter in determining the temperature difference required for a specific heat transfer rate, allowing engineers to design systems that can efficiently manage heat, particularly in high-performance electronic devices.

One-Dimensional, Steady-State Heat Transfer

This concept assumes that heat transfer occurs predominantly along one dimension and that the system has reached a state where the temperature profile does not change with time. These assumptions simplify the analysis by reducing the complexity of the heat conduction equations, allowing for easier modeling of temperature gradients and heat flow using a simplified thermal circuit.

Heat Dissipation in Electronic Components

Effective heat dissipation is critical in electronic systems to prevent overheating and maintain performance. This concept addresses the techniques and design considerations used to manage and remove excess heat from components, such as the use of fin arrays or heat sinks, while keeping the operating temperature below a material or device’s maximum safe limit.

Transcript

Please give Ace some feedback