12 volt switching power supply using LT3748
Using the LT3748 switching regulator controller specifically designed for the isolated flyback topology can be designed a very simple high efficiency 12 volt power supply project .
LT3748 drives a low side external N-channel power MOSFET from an internally regulated 7V supply. No third winding or opto-isolator is required for regulation as the part senses the isolated output voltage directly from the primary-side flyback waveform.
The LT3748 utilizes boundary mode to provide a small magnetic solution without compromising load regulation.
Operating frequency is set by load current and transformer magnetizing inductance. As you can see in the circuit diagram , this switching power supply project is very simple and require few external components .
This 12 volt switching power supply require an input voltage range between 36 and 72 volts and will provide fixed 12 volt output at a maximum output current of 2 amperes (around 25 watts maximum output power ) .
Transformer specification and design is perhaps the most critical part of successfully applying the LT3748. If you want to change this design to provide a different output voltage and/or current please take a look in the datasheet to see how to change critical parts for this project .