VAPOR CHAMBER DESIGN GUIDE

VC (Vapor Chambers) literally called steam chamber. In the industry, it is generally called flat heat pipe, temperature plate, soaking plate. With the continuous increase of chip power density, VC has been widely used in the heat dissipation of CPU, NP, ASIC and other large power devices.

1.VC is better than heat pipe or metal substrate radiator

Although VC can be considered a planar heat pipe, it still has some core advantages. It is better than metal or heat pipe. The surface temperature can be made more uniform (hot spots are reduced). Second, the use of a VC heat sink allows direct contact between the heat source and the device, thereby reducing thermal resistance; while heat pipes typically need to be embedded in the substrate.

VC compared with heat pipe and metal

2. Use VC to equalize temperature instead of transferring heat like a heat pipe

Heat pipes are ideal for connecting heat sources to the distal fins, especially for relatively tortuous paths. Even if the path is straight, more heat is used instead of VC for heat transfer requiring remote transfer. This is the key difference between heat pipes and VCs. The focus of heat pipes is to transfer heat.

 
                                                                                                             VC diffuses heat, heat pipe transfer heat

Of course, there are exceptions. When the cost is first, the two heat sources are close and the temperature is required to be uniform, the use of heat pipe is also an option..

3. Other considerations

Size - there is no theoretical limit, but VC used for cooling electronic equipment rarely exceeds 300-400 mm in X and Y directions. Thickness is a function of capillary structure and dissipation power. Sintered metal core is the most common type, VC thickness is between 2.5-4.0mm. 

Power density - the ideal application of VC is that the power density of the heat source is more than 20 W / cm 2, but in practice, many equipment is more than 300 W / cm2. 

Protection - the coating most commonly used for heat pipes and VC is nickel plating, which has the function of corrosion prevention and beauty. 

Operating temperature - although VC can withstand multiple freeze / thaw cycles, their typical operating temperature range is 1-100 ℃. 

Pressure - VC is usually designed to withstand a pressure of 60 psi before deformation. However, up to 90 PSI