How to make a pulsed AC/DC converter?

Question

Electronics

There is a device that consumes 3.3v, 400 mAh, and must receive energy from a 220v network, i.e. need to make AC/DC stepdown converter. The situation is complicated by the fact that there is little space for it in the case - 100x20x10 mm. What do you advise to do?

Answer 1

What is mAh? The current strength is measured in mA.
And so - use the filling of the memory from the phone.

Answer 2

The new Nokia chargers are thin - like giblets should fit into 10 mm.

Answer 3

LNK306 it produces according to a typical switching circuit 12V 120mA, this is 1.44 W, 3.3V * 0.4a = 1.32 W. We throw a small DC / DC 12V => 3.3V with an efficiency of 90% and the problem is solved.

Answer 4

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