日本語
Hi,
We are doing a Test PCB containing one Vicor BCM4414xH0E5035yzz module, which will feed 4 paralleled Vicor DCM3623x50M53C2yzz modules. (these are all DCDC modules)
The BCM module will dissipate 84W. Each DCM module will dissipate 43W.
We are going to need heatsinks on them. We think the best way would be to put 3mm NPT holes near the 4 corners of each module….and then use these to fit an aluminium heatsink plate over each module’s surface….ie screws and nuts/washers, to pressurize an aluminium plate against each module surface. Would you say this is the cheapest way to do it for this test (only) PCB?
Also, the BCM module that we are using is the “board mount” version. (pg 39 and 40 of the datasheet). It appears that holes 10,11,12 & 13 are for screwing the module to the PCB…..then PTH pads 1,2,3 & 4 are for power input and output. But what are the screws for on pads 1,2,3 & 4?.......since the “board mount” version "solders" into the PCB…so why does it have these 4 screws at pad positions 1,2,3 & 4?
Also, the BCM module diagram on page 40 of the datasheet appears to be trying to inform us what are the dimensions of the PTH pads……..can you tell what the PTH pad dimensions are from that diagram?.......surely a round PTH pad should be described by its drill diameter and its outer diameter. Unfortunately I cannot ascertain that info from the diagram, can you?
- Comments(1)
A****min
Feb 26.2020, 09:33:07
Thermal paste is only supposed to fill the imperfections in the surfaces, after the parts are clamped metal-to-metal anyway.
There should not be a measurable thickness of it after assembly.
You need some permanent pressure.
Or, use a heatsink bonding adhesive rather than thermal paste and just apply pressure until it is fully cured?
Make sure it's a proper one with high thermal conductivity though, there are a load of places selling silicone rubber based types recently which do not seem to have good characteristics, from what I've see so far.
