DC/DC Derating Help

I am currently trying to figure out how much power output I can push my 5v to 12V, 1 Watt, DC/DC converter.

Datasheet: https://www.digikey.com/product-detail/en/RE-0512S/945-1142-ND/2256322

I haven't really worked with DC/DC's much and in my current application I need to push this this DC/DC as hard as I can.

There is a graph which I have attached that is showing Derating for ambient temperature. From what I can gather from the graph is that if you are using the DC/DC in an environment which is 85 degrees C or less you can run the DC/DC safely at 100% output power.(in this case 1Watt of power). I have a hard time believing this as that's 185 degrees F and you can still push the DC/DC at 100%???

Can anyone point me in the right direction?

I need to push this this DC/DC as hard as I can.

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Nevertheless, allow yourself a good safety margin unless you want a short life for your converter. Does the datasheet indicate how long you can run it at 100%?

alec_t said:

Nevertheless, allow yourself a good safety margin unless you want a short life for your converter. Does the datasheet indicate how long you can run it at 100%?

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I agree. I don't find any information about how long it will last at 100% but they do reference some standards so I will check into. I'm not sure how to interpret their graph which i attached on my orig. post. Can anyone help with that?

The graph shows you should be able to run 'safely' (however that's defined ) at 100% for ambient temps up to 85°C, then at progressively lower % as temp increases, as far as 100°C at 30%, beyond which temp it's unsafe at any %. Do you trust the datasheet? Are you feeling lucky? Personally, I'd not want to run anything at 100%.

yeh. I agree. running anything at 100% is just silly. I'm going to probably just do a 50% derating and call it a day.

Basic power electronics principles apply. The cooler you keep the part the more power you can dissipate in it (which means more output power from the converter).

If you attach it to a larger heatsink (if it has a cooling surface) or cool it by removing hot air from it with a fan, you can run at higher output power without compromising life or safety.

One of the best tools you can have is an InfraRed pointer thermometer, and test run power components and measure the temperature of anything that gets hot. When it comes to heating of power componentns; "If in doubt, test it out".