Re: Suggestions for PSU improvements
On the EMI filter yeah probably all of the above listed.
Mostly now on the PCB but older (lower power) supplies did tend to have them.
What you find with the cheapie PSU's the positions might be on the pcb but not the components
(any supply like that the best place for it is the bin)
You may find this area skimped on component quality wise too.
heres an example of a cheapie "lets throw away the EMI filter" well half of it and use possiblely (more likely are) sub standard caps
(lowewr left hand corner, were the red white coil is)
just as a side point
this one was missing 2 resistors that would have forced equal voltage across each of the mains I/P caps, which probably explains the stuffed vented cap at the top
(No Mov's either)....
In short junk not worth fixing and there's a lot of it out there.

Active PFC (power factor correction)
Well found this link and it has a bit of a tutorial on it...the really good part is it has lots of chips listed and links to PDF's humm
Power Factor Correction IC's
Just click on the link at the top "View All Products In This Category" if you want to see the whole host of chips about 3 pages I think
This site looks like a handy one...why haven't I found it before LOL
just on your question of adding PFC, you might get away with Passive PFC
but Active is a whole different ball game from what I gather.
Its intended purpose really is to keep power companies happy not consumers from what I understand.
I think generally speaking there is really little benefit to the consumer and it more the fact laws have been pasted so PSU manufacture have no choice but to comply if they want to sell their psu's in certain countries.
Anyway thats the story as I understand it but not the guru on PFC either.
HTH Cheers
On the EMI filter yeah probably all of the above listed.

Mostly now on the PCB but older (lower power) supplies did tend to have them.
What you find with the cheapie PSU's the positions might be on the pcb but not the components
(any supply like that the best place for it is the bin)
You may find this area skimped on component quality wise too.
heres an example of a cheapie "lets throw away the EMI filter" well half of it and use possiblely (more likely are) sub standard caps
(lowewr left hand corner, were the red white coil is)
just as a side point
this one was missing 2 resistors that would have forced equal voltage across each of the mains I/P caps, which probably explains the stuffed vented cap at the top
(No Mov's either)....
In short junk not worth fixing and there's a lot of it out there.
Active PFC (power factor correction)
Well found this link and it has a bit of a tutorial on it...the really good part is it has lots of chips listed and links to PDF's humm

Power Factor Correction IC's
Just click on the link at the top "View All Products In This Category" if you want to see the whole host of chips about 3 pages I think
This site looks like a handy one...why haven't I found it before LOL
just on your question of adding PFC, you might get away with Passive PFC
but Active is a whole different ball game from what I gather.
Its intended purpose really is to keep power companies happy not consumers from what I understand.
I think generally speaking there is really little benefit to the consumer and it more the fact laws have been pasted so PSU manufacture have no choice but to comply if they want to sell their psu's in certain countries.
Anyway thats the story as I understand it but not the guru on PFC either.
HTH Cheers

Comment