Relationship between Copper Patterns and Temperature Rise of Printed Circuit Board for Small Surface Mount Electronic Components in Terms of Constriction Thermal Resistance

Abstract

In recent years, the circuit (printed board) designers play an increasingly important role in the thermal design of electronic devices. Generally, small chip type components generate but a very low level of heat. Lately, however, the heat generation density of small chip type components is rising along with the downsizing of electronics. Small chip type components have no cooling devices, and heat dissipation from the components occurs mainly through the copper pattern on the board. Therefore, if the design of copper pattern on the board is inadequate, generated heat from the components cannot be dissipated, thus running a risk of excessive temperature rise.
This paper discusses the relationship between the mounting pad shape and the temperature rise of the board, which can be significant in the thermal management of small surface mount components. Using the concept of constriction thermal resistance, the temperature of the component can be estimated easily without taking complex copper patterns into consideration.