Surface mount heatsinks

[jackorocko]

http://www.ohmite.com/catalog/pdf/d-sink.pdf

How does one go about soldering these onto a pcb? My first thought was heating up the ends of the tin rods, but after looking at my boards, this is gonna be nearly impossible since I have surface mount devices within an 1/8th inch of those tin ends.

Could I put solder on the board and then heat the heatsink up to a temperature beyond the melting point of solder and quickly set it into place and hope the solder melts before the heatsink cools to much?

 

[(*steve*)]

A reflow oven is probably the best bet.

 

[OLIVE2222]

Hi,

Yes reflow is the normal method however smaller components can suffer a lot because of the higher temperature to be used. Having 0402 sized components in the neighborhood of large ceramic QFN or BGA packages can already make them fail (immediately or in a very short term). Is there any manufacturer recommendation?

Olivier

 

[jackorocko]

http://www.avayanelectronics.com/Products/AE-STPR8811/AE-MDL-STPR8811_Manual.pdf

There is no specific instructions. Would it be unwise of me to use a heatsink that was glued to the top of the DRV8811 with thermal paste instead of this surface mount heatsink? From the datasheet I find it hard to believe this specific SMHS is actually doing to much since the distance from the bottom of the heatsink to the top of the DRV8811 would be a few mm of air.

The board will give you the options to use external Schottky diodes to remove heat outside of the device during asynchronous fast decay current recirculation. As a second measure, you can considerably enhance the system’s thermal impedance by adding a surface mount heat sink. It may not have been designed for the HTSSOP28 package, but boy does it do a good job! Take this design to the extreme of reaching the 2.5A mark by adding a fan. Mounting holes are spaced at 70 mm so that you can add a commercially available 24V from Sunon.

http://www.avayanelectronics.com/Products/AE-STPR8811/ae-stpr8811.html

 

[OLIVE2222]

Hi jackorocko,


If it's a one shot on an existing board probaly better to make a bit of heatsink surgery and indeed to glue it with thermal conductive glue.

http://www.farnell.com/datasheets/22500.pdf

Olivier