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it's a long time that I'm looking for a 220V - 5V 200mAh switching power supply and I haven't found my solution...

My board uses 140 mAh and it needs a small power supply whit no heatsink assembled on my board. I would be really happy if any one can suggest me a schematic of a small power supply that suit my board.

(The cost doesn't matter!!!)

---THANK YOU---

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    \$\begingroup\$ If cost doesn't matter then just buy a COTS adapter. Like, say, a cellphone charger. \$\endgroup\$ – Ignacio Vazquez-Abrams Oct 29 '14 at 17:38
  • \$\begingroup\$ I need to add it on my board!!! \$\endgroup\$ – kia_rst Oct 29 '14 at 17:39
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    \$\begingroup\$ shrug I'd rather add a USB connector than have to deal with high voltages on a PCB. \$\endgroup\$ – Ignacio Vazquez-Abrams Oct 29 '14 at 17:41
  • \$\begingroup\$ I have to, no choice here... \$\endgroup\$ – kia_rst Oct 29 '14 at 17:43
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Assuming you mean mA, not mAh, that's not much current. You can have a look at the chips by Power Integrations or Onsemi (NCP101x), for starters. Cheaper parts cost at the expense of more parts is achievable by using controllers without integrated switches (and external MOSFETs, of course).

enter image description here

It's good that cost doesn't matter, because the transformer will not be cheap in small quantities.

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  • \$\begingroup\$ Can you please tell me about the parts in the schematic? \$\endgroup\$ – kia_rst Oct 29 '14 at 18:14
  • \$\begingroup\$ what kind of transformer should I look for? (The numbers!!) \$\endgroup\$ – kia_rst Oct 29 '14 at 18:15
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    \$\begingroup\$ @kia_rst Data sheets are linked. Read them, check out the schematics and come back with a new question if something arises. Reference designs may include some parts you can buy our you may be required to go to a custom xfmr maker. Read the data. \$\endgroup\$ – Spehro Pefhany Oct 29 '14 at 18:21
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enter image description here

find a cell phone charger i.e this one can be your smps circuit so open any cell phone smps and replicate the circuit you will find but modify the regulator to get your desired current check the link below, thats all

http://www.homemade-circuits.com/2015/04/how-to-make-variable-current-smps.html

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Have you considered AC/DC power modules for PCB mounting?

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