After burning out a 3DR MinimOSD V1.1 from powering it for too long on the ground during testing a while back, I printed an enclosure kit with two large heat sinks for it.
The 3DR version of MinimOSD V1.1 (with straight video pins) sit in there nicely, it also accommodates some other vendors version 1.2 of the same PCB but with the 90-degree bend video pins. I tried with both, nice fit and keep the chips cool 
I can print one and ship to you including a couple heat sinks, if anyone is interested.
Regards,
Oscar
Comments
Hi Ozzy,
It would be better to heat sink from the bottom layer because the MAX7456 has a thermal pad soldered to both TOP and BOTTOM layers for heatsinking. You can stick a larger and thinner heatsink over the whole bottom layer and thus use it as a mounting plate. Heatsinking the MAX7456 case is not so efficient as heatsinking the thermal pad. And as mentioned above you don't need to heatsink the ATmega.
Best regards
Nick
What I would like to have in addition with such a case, is a way to block wrong pin connections by reversing Vcc and Gnd for example. Could be as simple as markings on the case next to the JR connectors and\or mechanically block reverse plugin.
Thanks Hein,
you can order it from here: http://tinyinvention.com/minimosd-v1-2-cooling-kit.html
Regards,
Oscar
mP1, the case is there so the heat sinks don't get knocked around by wires and what not, also makes the OSD easier to attach to surface, to grab and remove, etc.
Why do you even need the case, why not simply attach the heat sink ?
Hi Nathaniel,
The reason I kept the heatsinks below the case is to provide protection and support for it so it won't get knocked around in hard landings if the enclosure detaches from velcros somehow. The heatsinks are larger than the surface of the chips they are attached to, so I think they would still keep it quite a bit cooler even with the tall walls around them, turbulent airflow should have no problem getting there, the top of the heat sink is only 2mm below the lid.
Kolin,
The MinimOSD V1.1 was the warmest device on my whole drone while the whole system is powered on, it was even quite a bit warmer than my video transmitter after a couple minutes idling on the ground. My goal is to have a reliable device that can be tossed around and won't have heat issue even if you leave it powered on idling for long periods.
The enclosure does have large opening and space on both end of the enclosure, air flow is allowed to go through both under and top side of the PCB.
Oscar
Atmega don't need heatsink. Maxims's IC could use one, but it is already cooled to PCB by thermal pad on underside. Old version of minimosd with tiny linear 5V regulator needs cooling, or better replace by regulator by bigger 75M05. I never had issue with newer minimosd with switchmode power supply.
Nice case. But actually it is good for mechanics, bad for heat. You enclose something generating heat in case from thermal "non conductor".
Oscar,
I like your idea, and the design. Do you have any data that shows it actually improves cooling while stationary? Also, wouldn't it be better to have the heat sinks exposed above the case surface exposing them to any available airflow?
Regards,
Nathaniel ~KD2DEY
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