11-19-2011 10:20 PM - edited 03-16-2019 08:08 AM
Hi. I've got an application where I'd like to power SPA3102 ATAs from an existing 12V DC power supply. Looking inside the unit, I see it uses an AP1513 switching regulator that has an input range of 3.6 to 18V, so it seems conceivable that 12V would be fine. However, I'm not sure about the support components.
Does anyone know the acceptable input voltage range for the SPA3102? Or know where to find out?
Thanks,
Adrian.
11-21-2011 12:26 AM
These are notes reported on original data sheet:
Power supply
Power consumption: 5W
Switching type (100-240V) automatic
Power adapter: 100-240V, 50-60 Hz (26-34 VA) AC input
DC input voltage: +5V DC at 2.0A max
Different values can damage the SPA.
You can realize a simple circuit with LM 7805 to get 5v from 12v.
Regards.
11-21-2011 01:06 AM
Thanks for your response Daniele. I understand that the datasheet specifies +5V, but in reality it's never as simple as specify a single voltage (that is, no power supply will output an exact voltage, especially under varying load conditions). All device can accept a range of voltages, some much smaller than others.
Thanks also for your suggestion of the 7805, but I was actually thinking of using a 12 to 5V DC-DC converter (like this one: http://www.current-logic.com/shop/index.php?main_page=product_info&cPath=4&products_id=204). I discounted a linear regulator such as the 7805 because it will dissipate a whole bunch of power/heat. Dropping 7V at 2A peak is 14W! Also, the 7805 in TO-220 packages are usually rated at only 1.5A, and going to the TO-3 package with appropriate heat sinking is a real pain to deal with (and are quite physically bulky).
But either way, seeing as the SPA3102 already has a switching regulator built it, it seems superfluous to use an external regulator.
I guess what I'm really asking is: Where can I find the "absolute maximum" ratings for the SPA3102? This level of detail doesn't seem to be covered on the standard datasheet.
11-21-2011 03:46 AM
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