Electronic – AMS1117 33 sot223: is it ok with ceramic capacitors

ceramicelectrolytic-capacitor

This is the datasheet of voltage regulator that I would use:

http://www.advanced-monolithic.com/pdf/ds1117.pdf

Is it possible to exchange that 22uF with an equivalent (or larger) ceramic instead of electrolytics? Cause I would use 1206 SMD components.

Also, in some websites I did find schemas with 2 capacitors on INPUT and 2 on OUPUT, on parallel, both of 22uF + 100uF.

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In effect, I did print same pcb layout (feeded power from a Samsung Charger via MICROUSB and converted down to 3V3) with electrolytics capacitors and it works very well (tested with a multimeter, 5V on INPUT and 3V3 on output). Is it an exageration?

Thank you for both the answer

Edit: another schematic with this AMS1117 is the module provided on Aliexpress.

This is the image (mirrored…), you can read 104+106 on input and same on output.

I did test them from a friend and seems to work… What do you think about them?

On another image, seems clear that 104+106 on input and 104+106 on output. Is possible that supplier does not respect the datasheet?

enter image description here

enter image description here

Best Answer

No, not necessarily. You can replace the electrolytic capacitor with an equivalent ceramic with a 0.33 or 0.5 ohm resistor in series. The datasheet only mentions tantalum capacitors and you should take that as an enormous red flag. Too-low ESR means that the regulator could be unstable or only conditionally stable (could oscillate under different load or temperature conditions).

Note that a 22uF ceramic may not be equivalent to a 22uF electrolytic. Especially for smaller types run close to their rated voltage the capacitance can be much less than the marked value. Always check the capacitance vs. voltage curve for the proposed part.