Who knows a minimalistic power supply 220V to 3.3V for MK with a circuit consumption of 100mA?

Question

Power Supply

Good day.
Can someone tell me the scheme of a stable power supply without galvanic isolation? With a minimum dimension of 1 cm3 without the need for a metal housing for heat dissipation. To be able to power STM8 microcontrollers.

Answer 1

I would first do something like this:
radiostorage.net/?area=news/2065
Then something like this:
www.chipdip.ru/catalog/ic-stabilizers/?p.1545=3.3
Thus, we get the power supply immediately with two sufficiently running voltages - 12 V (from the first "stage") and 3.3 V (from the second "stage")
Although, you can probably find a circuit similar to this one:
radioskot.ru/publ/bp/bestransformatornyj_blok_pita...
But with output 3.3 instead of 5 like the LM7805.
The main essence of these circuits is very simple - in order to lower the input voltage to the permissible for the stabilizer microcircuit, it is limited by the drop across the resistor and / or with the help of a divider, and the stabilizer smoothes the resulting spread due to the load and produces the required output.