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How to get 5v AC from 230v AC line by using resister....

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sajeev

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how to get 5v

Hi
I am doing a project on microcontroller.How to power the microcontroller board without using transformer.I mean how to get 5v ac from 230v av.Whats the design of the circuit?
 

how to get 5v from 230v

what is the required maximum current. and also it is danger. i suggest u to use some small type of smps with tiny swith .which will not consume much space


sajeev said:
Hi
I am doing a project on microcontroller.How to power the microcontroller board without using transformer.I mean how to get 5v ac from 230v av.Whats the design of the circuit?
 

230v ac line

grittinjames said:
i suggest u to use some small type of smps with tiny swith
what is the smps ??
 

    V

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230v to 5v without transformer circuit

DO NOT USE the circuits suggested in the link given by IanP. THEY COULD KILL YOU. In my opinion it is irresponsible of Microchip Inc to publish those circuits (they do mention the danger unless you use an isolation transformer, but why then call it a "tranformerless" design? Ridiculous).

Why? The mains N line is in and around ground potential (as you would be, were you to stand in bare feet) but the L line oscillates between +325 and -325 volts with respect to ground. [325=230xSquareRoot(2), because the 230 is root-mean-square). The suggested power supplies would feed that voltage, and another that is just 5 volts different--but of course it also is oscillating up and down at a lethal level. Put your finger on that power supply while in bare feet, and it's the last thing you'll ever do. Even if you wear rubber shoes, but your other hand touches a metal bench or something, same result. The circuits would be somewhat less lethal to you if L and N were interchanged, but it's still quite liable to kill your microcontroller. (By the way, you probably mean 5V DC, not 5V AC).

Stay alive: buy or build a proper power supply with a transformer in it. If you don't understand why, or if you don't know what smps might stand for, you have no business monkeying about with mains supplies. I'm deadly serious about this.
 

ac230v to 5v circuit

I'm sorry but I got the feeling that you don't know much about power supplying. Building a circuit like the ones suggested on a testboard and then using it for microcontroller projects just like that is dangerous. Playing with the mains can really kill you! Buy a 5 V supply from the store instead. I know this is not what you want to hear but it's for your own safety.
 

how to get 5v easy

i understood u dont have much idea about power supply . at athis stage it is better to buy a supply from near by shop
im not getting a man dosent know about smps is working with UC.
surprising

showntimoon said:
grittinjames said:
i suggest u to use some small type of smps with tiny swith
what is the smps ??
 

230v micro controller power supply

grittinjames said:
what is the required maximum current. and also it is danger. i suggest u to use some small type of smps with tiny swith .which will not consume much space


sajeev said:
Hi
I am doing a project on microcontroller.How to power the microcontroller board without using transformer.I mean how to get 5v ac from 230v av.Whats the design of the circuit?



HI,
I need to power PIC without using transformer.I have seen the circuit with capacitor-resistor parallel arrangement.But i dono how it works and how much current i can get from it?Any idea of the design details.(I just dont want to copy blintly without knowing the working)
 

+5v off of ac line

Go out and buy an adaptor with voltage adjustment.

Or

Find a 7.5V,9V or even 12Vdc adaptor then use LM7805 to regulate the voltage to 5V.

Easy and safe !

Don't mess with main voltage unless you know exactly what you are doing !![/GVideo]
 

i need a 230v AC to 5v AC transformer but i really don't want to use transformer instead i want to use some thing else but safe still. can some help me?

i want to use the ADC of a micro controller.my biasing voltage is 5v so i cant go above it but if i use transformer the whole design gets very bulky.
 

Your question seems a bit off-topic here, because it's apparently related to voltage measurement rather than power supply.
Some previous topics discussing measurement transformers and other options:



Also a differential amplifier with resistive voltage divider can be an option, but it must have a good common mode rejection.
 

    V

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