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Topic: 24V PSU + 7809/7812? (Read 832 times) previous topic - next topic


I had never heard of DC/DC converters before Heke's post, but now I see lots of options including these: http://www.adafruit.com/products/1065

Adafruit only carries the 5V and 3.3V versions of the above, but it seems like I would want the 9V version (TSR 1-2490 http://www.adafruit.com/datasheets/tsr1.pdf) if I am going to connect it to Vin, right?

And I'm curious, other than heat and inefficiency, what is wrong with the 78xx regulators for this type of application? I see that they are terrible with large voltage differences between input and output, but are there other reasons not to use them?

Thanks again.


If you know the approximate current draw, you can put a power resistor in series with the regulator input lead to handle some of the power dissipation.

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