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public
join:2002-01-19
Santa Clara, CA

1 recommendation

public to tempdays

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to tempdays

Re: Difference between transformer & SMPS 12V power supply ?

said by tempdays :

things fail based on parts count.
the more parts a circuit has, the more parts the circuit has that can fail.
plus more connections between them.
lower parts count means longer life.

Which make linear supplies with hot regulators fail.
Shoddy workmanship is more likely in hand soldered linear supplies.

Switching supplies fail due to voltage spikes overstress from poor layout, and excessive ripple current in fake or underspecified capacitors.
There are no hot regulators. Heat is a problem when more lossy parts are substituted by the assembly vendor.

If EMI or surge robustness are a concern, external components can be added.

Linear supplies can also be used as space heaters, or with a piece of rope in marine applications.

EliteData
EliteData
Premium Member
join:2003-07-06
Philippines

EliteData

Premium Member

said by public:

...Linear supplies can also be used as space heaters, or with a piece of rope in marine applications.

lmao !

SmokChsr
Who let the magic smoke out?
Premium Member
join:2006-03-17
Saint Augustine, FL

SmokChsr to public

Premium Member

to public
This past week I was in Vegas at a Broadcast trade show looking at new transmitters. One of the things I found interesting is in the high efficiency power supplies they have done away with the rectifiers, replacing them with MOSFETS and switching them on the zero cross so they can eliminate the loss inherent in a diode.
tedmarshall
join:2000-12-02

3 recommendations

tedmarshall

Member

said by SmokChsr:

This past week I was in Vegas at a Broadcast trade show looking at new transmitters. One of the things I found interesting is in the high efficiency power supplies they have done away with the rectifiers, replacing them with MOSFETS and switching them on the zero cross so they can eliminate the loss inherent in a diode.

This is the latest thing. Here's a controller to run 4 MOSFETs as a high efficiency full-wave bridge rectifier: »www.linear.com/product/LT4320.
lutful
... of ideas
Premium Member
join:2005-06-16
Ottawa, ON

lutful

Premium Member

said by tedmarshall:

said by SmokChsr:

This past week I was in Vegas at a Broadcast trade show looking at new transmitters. One of the things I found interesting is in the high efficiency power supplies they have done away with the rectifiers, replacing them with MOSFETS and switching them on the zero cross so they can eliminate the loss inherent in a diode.

This is the latest thing. Here's a controller to run 4 MOSFETs as a high efficiency full-wave bridge rectifier: »www.linear.com/product/LT4320.

Linear is my favorite company and I like that particular IC very much.

GaN is becoming viable for very high power. This tiny demo unit converts 5KW at 98.5% efficiency with 8ns turn-on and 3ns turn-off time.

You can't use that as a boat anchor but 5000W*0.015=75W of waste heat may warm your heart.