230V power supply to Arduino

[axillent]

@Tibus SR086 able to provide 100mA from 9-50V. For example you can set it to provide 20V and add DC-DC step-down for example based on MP2359. This will give you current-UP benefit at 5V etc. 20V@100mA will give you 5V@360mA maximum with 90% efficiency

My preference in your case LNK306, you can get directly up to 350mA. Using ceramic capacitors and SMD inductors you will fit in 7-10mm height (see one of my picture above)

And at last. Why not SSR? What type of the load do you have?

[Tibus]

@axillent Thank's verry much. I didn't know the current up benefit of a step-down. I think it's the key of my problem!
I'll test the lnk306. Hope It will work for my project.

For my "in wall module", it's just lights so no problem for an SSR. But for the wall plug, The user chose the load they want... so if it's a TV or a washing machine or a power supply, I read an SSR is not verry good for these things...

[axillent]

@Tibus YAW
For LNK take a look for AN37, especially optimization at table 9
an37-linkswitch.pdf

SSR is fine for most of the loads. But you need to follow recommendation of their use and to control limitations (like maximum ratings and heat dissipation)

[axillent]

I'm expecting to receive my SR086 and SR10 this week
I have a plan to run some tests

[klim]

Regarding the SR10 i've already here a few, but just no time to build up something ;-(
The more i'm curious for your results.

[axillent]

@klim I made a test PCB

I succeed to get about 34mA with 1uF capacitor and probably it will provide 40mA stated in the datasheet
it is not possible to use it directly without an additional LDO or step-down because of a very high ripple.
According to my measurement ripple is 2.8V with 12.6V average output (figures in table should be multiplied by 10):

consumed power from AC is 0.8 W with 36mA output
this means 57% efficiency, not bad for such thing

[Tibus]

hox much current could you get with a LDO ort step-Down to 5V or 3.3V? 80ma?

[axillent]

@Tibus the output current from SR10 is depends on the capacitor and rectifier. See the table inside the datasheet

with step-down I can get from my prototype about 100mA at 3.3V
with LDO you will get out as many as you get in minus quiescent current of LDO itself

[axillent]

I made a success by replacing polymer capacitor by ceramic one in the usage of SR10
it leads to a dramatical decrease in needed space. I believe that it will be the smallest AC-DC fotprint

But still I have som problems with DHT sensor to work from SR10 (http://forum.mysensors.org/topic/971/small-wall-outlet-sensor-node)

[jeylites]

@axillent

I like the case you are using. Where did you get it from?

[marceltrapman]

@jeylites said:

@axillent

I like the case you are using. Where did you get it from?

It looks like it was printed.

If so, are you willing to share the files?

[axillent]

yes, all cases are printed
sure, I can share if you need
the case developed for a particular custom made PCB

[marceltrapman]

@axillent said:

the case developed for a particular custom made PCB

I understand but the design is still a good starting point :)

[axillent]

@marceltrapman sure, just give me some time to publish it on thingerverse

[marceltrapman]

Nice, thanks...

[Magiske]

Was looking into the same and ordered 2 different 230/110v to 5v of ebay to get a cheap 5v powersource. Just got them today.

The White around $1.5 and the Black was $1.0

Before wirering everything up, I just added the smaller white's pcb to the black case incl. radio and pro mini. And there is room for a bit more.
So unless it goes up in flames I will try to create a default sensor node.

[Vladut Grecu]

If you don`t go over 50-60% of the amps that that charger can output, there will be no problems. I suggest you replace the capacitor on the 5V area with a bigger one and change the 220/110v capacitor with a higher quality one. What I figure from your pictures is that the black charger doesn't have a bridge rectifier.. It's safer for you to use one. (Don't forget about the fuse)

[ferpando]

Anyone tested one of these cheap power supplies with an osciloscope?
I got a couple yesterday but not sure if they are good enough

[gadu]

I've seen these and also got interested. Any input on these is appreciated.

[Jan Gatzke]

@Magiske I am using a power supply similar to the black one. My one has a fake optocoupler. The output voltage is unregulated. Have a close look before using this pcb. ;)