Tuesday, October 8, 2013
POWER CONVERTER TOPOLOGY ELECTRONIC CIRCUIT DIAGRAM
POWER CONVERTER TOPOLOGY and MOSFET SELECTION FOR 48-V TELECOM APLICATIONS ELECTRONIC CIRCUIT DIAGRAM
Output voltages are frequently 5V and below with 3.3V probably the most common requirement, and 2.5V gaining in popularity. If a processor is on the card, voltages as low as 1.3V are not unlikely. One common approach is to regulate a distributed power bus, say the 5V rail, and then use non-isolated DC/DC converters to generate lower voltages. With the tendency away from 5V, the 3.3V rail is beginning to serve as the distributed bus, although, from the power supply designer’s perspective, this is not the most of desirable situations.
Fairchild has recently introduced a family of high voltage MOSFETs ranging from 80- to 200-V drain voltage specifications. This application note will provide information helpful in the proper selection of FETs for primary side switches – available in various types of 48V power converters.