Lytron’s new CP40 copper etch cold plate offers a combination of high performance, water compatibility and a low pressure drop. With a thermal resistance of only 0.0015°C/W at 3 gallons per minute (gpm), it is suitable for demanding electronics cooling applications. The unit’s performance is primarily achieved by crossed microchannels, which create turbulent fluid flow. The microchannels are etched into the copper beneath the entire surface of the cold plate, resulting in excellent thermal uniformity. The copper's high thermal conductivity enhances the performance and, because the cold plate is constructed entirely of copper, it is compatible with untreated water and many other common coolants.
The unit has a pressure drop of 5 lbs per square inch (psi) at a flow rate of 1 gpm. Although the individual channels are small, the overall cross-sectional area is large as the water flows through many paths simultaneously. The low pressure drop allows the CP40 to be used at flow rates up to 6 gpm, resulting in a normalized thermal resistance of only 0.058°C-sq in/W. The cold plate’s proprietary manufacturing process results in a 100% metallurgical bond between the copper plates to ensure a leak-free and highly reliable product.
The CP40 is only 0.10-in thick and weighs just 2.2 lbs. The standard CP40 measures 6 in × 9 in., making it is suitable for large area cooling or multiple components. It is predrilled to accommodate common power electronics packages. The cold plate is flat on both sides to enable dual-sided mounting. A choice of straight or beaded fittings facilitates integration into cooling circuits. For OEM volumes, the CP40 can be customized to virtually any size (up to 7 in. × 11 in.), shape and thickness. Holes or drillable areas can be added by including “islands” in the etch pattern.