I need to know if LM2596T-3.3 voltage regulator works with AC electricity. Datasheets doesn't specify the type of current.

 

That chip is used to create DC to DC converters, so I'm thinking the answer is no.

 

I would need an voltage regulator to change from 12V AC to 5V AC. Do you know a model?

 

Regulating AC is very difficult, and not my area of knowledge, are you sure you need regulation?

If not a simple step down transformer might do what you need.

 

For 12VAC to 5VAC, use a step-down transformer.
For 12VAC to 5VDC, use full-wave rectifier, smoothing capacitor, LM7805 linear voltage regulator.

 

I would need an voltage regulator to change from 12V AC to 5V AC. Do you know a model?

Are you taking about 60hz (or 50hz) power line AC? It is unusual to see a need for 12V to 5V ac. What is the application?

 

In my country on the power outlets we have 220 V DC. I have an old laptop charger that take this 220 V DC and outputs 12 V AC. However I have a device that needs 5V AC. I need to step-down the 12V AC to 5V AC. I can't find AC-AC step-down.

 

I can't find AC-AC step-down.

It's called a transformer.

 

In my country on the power outlets we have 220 V DC ...

That doesn't sound right. I though that issue was settled at the end of the 19th century where Edison's DC power distribution lost to Westinghouse's AC power distribution. Why would any country distribute DC Power?

 

I made a mistake on power outlet we have AC. We call alternating and continuous current not direct current, so that's why I made this mistake

 

Now that we know it is AC you can use a transformer to reduce the voltage. With a input to output voltage ratio like that (about 40:1) you are going to need a transformer.

 

You can buy an AC to 5VDC adapter at a second hand store at a very affordable price.

 

In my country on the power outlets we have 220 V DC. I have an old laptop charger that take this 220 V DC and outputs 12 V AC. However I have a device that needs 5V AC. I need to step-down the 12V AC to 5V AC. I can't find AC-AC step-down.

Now, why would a Laptop Charger give 12 Volts AC ? Or is it 12 Volts DC?
Does your Device require 5 Volts AC or 5 Volts DC?