is anybody there make transformerless power supply?
What is the the max current for power up arduino pro mini 5V/16MHz?
can somebody put here scheme for power up pro mini 5v with transformerless adapter, only 4 diodes to make ac to dc and other parts of electronic that is needed in scheme?
Do you want to power the Arduino directly from the mains ? 110V or 230V ac ?
That is possible, but dangerous. A capacitor is used to lower the voltage and current.
hi, try the cheapest power grid (220V/110V) -> USB (5V) charger. small, easy to hack, ready for use :).
Max current is 200mA.
i need transformerless scheme, not with transformer, and it would be nice that scheme is with potentiometers for output DC voltage and current so that i can connect some servo motor which use more current and small things like diodes which use small amount of current.
example: if i want make bulb dimmer of 220v on the ceiling, on the lamp, i need something without transformer that i can put mini arduino and transformerless power supply in lamp, and put pir sensor in all this, so when i open any door in hallway that my bulb is turn on.
i think that the biggest consumer for arduino are servo motors (about 2A) if i'm not wrong...
Sorry, but that is not possible.
why it's not possible, there is many transformerless schemes on net but i didn't find one with potentiometers. And you can be more specific, what exactly is not possible.
Are you looking for something like this?
Features:
"RECOM Power RAC Series 1,2, and 3 watt AC/DC Converters are single output ultra-compact universal input AC/DC Converters for PCB mounting. Features include high efficiency, low standby power, and high operating temperature. The RECOM Power RAC 01, 02, and 03 Series also feature a built-in EMC Class B filter and are EN and CE certified. Output voltage range is 3.3VDC to 24VDC, including a 3.8VDC version for battery chargers and GSM modems.
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RECOM Power RAC Series 1, 2, and 3 Watt AC/DC Converters now include the new RAC02-SC/277 and RAC03-SCR/277 Series with a wider input voltage range suitable to customers worldwide and can also be used in lighting."
Tony5:
why it's not possible, there is many transformerless schemes on net but i didn't find one with potentiometers. And you can be more specific, what exactly is not possible.
Very funny, normally I am the person that asks for more details 
A switching power supply doesn't need the big transformer, but it still has a small transformer.
I thought that you didn't want a transformer at all. It is possible to use a capacitor to lower the voltage, but that can only provide perhaps 20mA which is not enough for the servo motors.
When you are okay with a switching power supply, you can buy it anywhere. They are more common than the big old transformers of the previous century.