Hello,
I'm tying to incorporate a power supply into PCB to feed the MCU and components directly. Doing that with old and heavy Ferrite Core Transformer have no science and is easy but they are bulky and heavy, since current is variable and sensitive components are in use i need to build a stable and isolated power supply with some protections.
Saying that i'm looking to build a power supply like now days commun ones. Problem is i have no clue how to do that. Pulse Transformer, and correct me if i'm wrong are what they use inside DC power supplies. Still they have use a lot of components and a whole science behind that design to it work correctly.

I have looked at reference designs for 5V like: https://www.digikey.com/reference-d...c-dc-conversion/ac-dc-smps-single-output/1687
Looking at schemantics looks simple to replicate but no clue what things are doing, all i know is the IC turn on and off to cut down voltage but still i don't know what components must be used to set it correcly. With same transformer is it possible to generate different voltages? Or each transformer have it voltage rated? Also how they know and set the rated current?
I haven't find any 3.3V reference design so far, also a problem i found is each design use a propertary IC or transformer that is hard to source with low avaliable quantities.

Overall i'm looking for a power supply with the following features:
Isolated 3.3VDC @ 2A
Easy to source, commun/generic components

Does anyone have a good material that can share in order to learn more about this type of power supplies?

 

Input Voltage must be 110v-230v (Universal)

 

You can take the charger 2A for a mobile phone and complete it with 10W, isolated dc / dc with an output voltage of 3.3V. So it will be easier.
I am sorry.

 

Input Voltage must be 110v-230v (Universal)

Given your level of knowledge you should not be attempting this. A mains supply has a large amount of energy available and if anything is a bit wrong it will go bang and release the magic smoke. They are inclined to this even when well designed.

Large areas of the circuit are at mains voltage and unsafe to touch and, further, they generate large voltages, up to 600V, and have the capability to release the magic smoke from anyone not used to working with such circuits.

Buy it, don't build it.

 

I agree with AH. Buying ready-built will also be cheaper than sourcing all the components and building it yourself.

 

Given your level of knowledge you should not be attempting this. A mains supply has a large amount of energy available and if anything is a bit wrong it will go bang and release the magic smoke. They are inclined to this even when well designed.

Large areas of the circuit are at mains voltage and unsafe to touch and, further, they generate large voltages, up to 600V, and have the capability to release the magic smoke from anyone not used to working with such circuits.

Buy it, don't build it.

I agree with AH. Buying ready-built will also be cheaper than sourcing all the components and building it yourself.

I agree with both, still it must be embedded into same space/pcb.
Is this module a good solution? http://eu.mouser.com/ProductDetail/...aalG5TUgH52QN1%2bIKAVjaz8zbcPMDAqX5PxnasLTw==

 

That looks good, if it fits the space you have. It may need some space around it for cooling.

 

If 2.5A is suitable then, yes, it will do the job. Note that the PCB design needs to keep the line input tracks well away from the rest of the circuitry. You may find this a useful guide.

 

Hello,
I'm tying to incorporate a power supply into PCB to feed the MCU and components directly. Doing that with old and heavy Ferrite Core Transformer have no science and is easy but they are bulky and heavy, since current is variable and sensitive components are in use i need to build a stable and isolated power supply with some protections.
Saying that i'm looking to build a power supply like now days commun ones. Problem is i have no clue how to do that. Pulse Transformer, and correct me if i'm wrong are what they use inside DC power supplies. Still they have use a lot of components and a whole science behind that design to it work correctly.

I have looked at reference designs for 5V like: https://www.digikey.com/reference-d...c-dc-conversion/ac-dc-smps-single-output/1687
Looking at schemantics looks simple to replicate but no clue what things are doing, all i know is the IC turn on and off to cut down voltage but still i don't know what components must be used to set it correcly. With same transformer is it possible to generate different voltages? Or each transformer have it voltage rated? Also how they know and set the rated current?
I haven't find any 3.3V reference design so far, also a problem i found is each design use a propertary IC or transformer that is hard to source with low avaliable quantities.

Overall i'm looking for a power supply with the following features:
Isolated 3.3VDC @ 2A
Easy to source, commun/generic components

Does anyone have a good material that can share in order to learn more about this type of power supplies?

You won't make one for less than a ready made one, like a phone charger which can be alterted to give out 3.3V easily..

 

That looks good, if it fits the space you have. It may need some space around it for cooling.

If 2.5A is suitable then, yes, it will do the job. Note that the PCB design needs to keep the line input tracks well away from the rest of the circuitry. You may find this a useful guide.

Yes 1A would do the work, but i like to keep a good margin.
My ideia is use bottom layer to AC and top for DC. Also i will design a cut on PCB in the middle of the module like they do with transformers on PSUs, that should do the work. AC will only go to module input and end there, distance to near DC will have several cm, all the rest of the PCB will be DC

You won't make one for less than a ready made one, like a phone charger which can be alterted to give out 3.3V easily..

I know that, sometimes i ask myself how is possible to build something that work so cheap... Like 5V phone charger tiny and cost 1 to 2€ complete product (China)...