Demonstration circuit 2821A is a compact no-opto isolated flyback converter featuring the LT8302. The DC2821A outputs 12V, and maintains ±1% (typ) regulation with a load current from 5mA up to 1.4A and over an input voltage from 4V to 28V. The output current capability increases with the input voltage.
Transformer leakage inductance causes a voltage spike on the primary side after the power switch turns off. To limit this leakage inductance spike within the MOSFET voltage rating of 65V, an RC snubber and a TVS clamp are installed to damp the ringing and clamp the MOSFET drain voltage to a safe level.
The demo circuit can be easily modified for different applications using predesigned transformers.
The LT8302 data sheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with the quick start guide for DC2821A.