details about transformerless power supply in decoration lights

Hello sir

I usually observed many of the decorative light arrays or chains with multi coloured or single colour light of 50 , 100 or 200 l.e.d. etc , that they have a circuitry to control the lighting pattern with a press button (micro switch) mounted on circuitry box . . . Inside the box i found a small chip like black colour structure where power is connected from a.c. mains 220 volts directly to the chip and direct outlines connected to light chains , it may be 3 or 4 or 5 depend on colour used , pattern of lights does fade in fade out/blinks/lights up one by one etc etc etc . . so how the circuitry inside chip works without high current power supply directly (as we already know about characteristics of transformerless power supply) . . please comment thanks

1. Many LED's are usually connected in series (connecting LED's directly in parallel without balancing resistors is never a good idea)
2. A small flyback transformer is probably what's converting the voltage. Like a wall wart.

what kind of transformer it is actually ? i never heared & too watching the circuit but a single PCB with built-in chip is here only , nothing more than that i can see all around it , no coils nothing then where is the transformer ?

here L.e.d.s are in parallel but all have 1k resistor with them . .

Does the cable look like it has a lot of little wires? Because then it might drop the voltage down to 12v or something and drive only 4 LED's at a time.
If you have a watt meter now is the time to use it. LED's don't draw much power, so a cheap switching buck voltage regulator in the 1-10 watt range could work fine, even though it might have a terrible efficiency figure.

rajaram04 said:

Hello sir I usually observed many of the decorative light arrays or chains with multi coloured or single colour light of 50 , 100 or 200 l.e.d. etc , that they have a circuitry to control the lighting pattern with a press button (micro switch) mounted on circuitry box . . . Inside the box i found a small chip like black colour structure where power is connected from a.c. mains 220 volts directly to the chip and direct outlines connected to light chains , it may be 3 or 4 or 5 depend on colour used , pattern of lights does fade in fade out/blinks/lights up one by one etc etc etc . . so how the circuitry inside chip works without high current power supply directly (as we already know about characteristics of transformerless power supply) . . please comment thanks

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The said circuits chip is powered by a resistor and zener diode combination where the supply to the chip is arround 5 volts and consumption is very less. Next the outputs are directly connected to gates of triacs of TO92 package which naturally can drive up to 20 watts without any problems. The led's are connected in series for a resultant of 110 volts where the common supply is rectified to half wave by passing through a single diode in series.
Cheers

Oh, and also, some very small inductors can be completely enclosed in a surface mount package the size of a capacitor.
But pranam77's answer (which is pretty much what I said about the led's in series) is probably what they used because it's just simpler.