Power Converter Topology and MOSFET for 48-V Telecom Systems


Posted on Feb 5, 2014

A typical specification can range from a low of 36V to a high of 72- with a 48-V nominal. In some designs, transients in excess of 100V need to be considered. Most of these designs will require input to output isolation of up to 1500V. Output voltages are frequently 5V and below with 3. 3V probably the most common requirement, and 2. 5V gaining in popularity.


Power Converter Topology and MOSFET for 48-V Telecom Systems
Click here to download the full size of the above Circuit.

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.




Leave Comment

characters left:

New Circuits

.

 


Popular Circuits

Complementary-output-variable-frequency-inverter
Wheel Of Fortune
50 MHz range frequency counter using ATtiny45 microcontroller
700w-power-amplifier-with-2sc5200.html
serial communication on atmega3216
Adding 1 PPS and 10MHz Outputs to the Z3801A
NSH Field Strength Meter
XTR112 114 without external transistor circuit diagram
Single-phase motor energy consumption of the two brake circuits



Top