What heat sinking measures are recommended?
Heat dissipation will occur naturally via convection to the air surrounding the board and via conduction to the PCB. Additional heat sinking may be required depending on clock rate and output level. Various methods can be used but consideration must be given to the constraints of space and amount of air circulation. Several methods are outlined below. 4.11.1 Bonded heat sink A metallic-fin heat sink can be bonded directly to the chip package with thermally conductive adhesive. 4.11.2 Using the PCB as a primary heat sink The material used in the manufacture of the PCB will also have a major effect upon the performance of the PCB as a heat sink. Where an FR-4 epoxy glass laminate PCB is used, an area of approximately 26cm2 will be required to dissipate 1 watt, but materials specifically designed for thermal management applications can achieve an equivalent dissipation over an area as small as 6cm2. 4.11.3 Heat transfer through a PCB mounted heat shunt The PCB can alternatively be used to
