TOPSwitch drain voltage max = 700V
Hello
Please can you assure myself that the TOPSwitch range is ok for UK mains use for sub 30W offline flybacks?
Is their any mileage in the satement that powerint.com PWM controllers are designed primarily for use with the lower USA mains (110VAC)?
The first problem I see is the limited maximum Drain voltage of 700V.
-ideally, for UK mains, this needs to be about 850V (minimum).
-The low maximum drain voltage of 700V, means that in UK the RCD snubber will end up dissipating more energy than if a higher drain voltage were allowed.
Also, the low drain voltage limit of 700V puts a limit on the available transformer turns ratios and output voltage levels in UK.
So can you assure us that TOPSwitch is OK for UK mains use at 230VAC?
Comments
I know there are billions of PI products in use, but isn't it true that most PI sales are for TNY switch and LNK switch, where they are used for small (1 to 4W) bias power supplies inside 100W+ offline SMPS's?
I am not interested in these very low power applications, where the controller and on-chip FET are not stressed very much.
Please can you tell me how many of PI sales are for PWM controllers which are being used in offline SMPS's of 15W and more?
Hi,
Almost all Power Integrations products (except for the DPA switch family which is for low voltage DC-DC application)are designed for universal input voltage range (85-265VAC). You can often exceed this range by making suitable changes in the circuit.
The voltage seen by the MOSFET is the sum total of the input rectified DC voltage, the reflected primary winding voltage (termed as VOR in PI Literature) and any additional voltage due to leakage reactance of the transformer. Our design tools as well as design guides (application notes) explain how these parametsrs are to be selected.
We have a large number of reference designs on our web site and a large number of those are supported with a complete engineering report. I suggest you review these designs and reports to satisfy yourself.
http://www.powerint.com/en/design-support/reference-designs/design-examples
Alternately we have application labs/ staff in several places in Europe, which support our major customers in Europe. Our engineers will be happy to answer your questions. Please contact our office in your country directly to speak to a sales/applications engineer who will be able to provide you additional information useful for you to make your decisions.
Regards
PI-Sarek
There are billions of PI products has been used in world wide off line power converter applications, and the major portion of these billions PI products are used in the high voltage power line countries.
There should be no problem to use TOPSwitch in UK applcation as long as a designer uses PI Expert software as a design guide.