Demonstration circuit 1643A is an isolated flyback converter featuring LT3575, a monolithic switching regulator specifically designed for the isolated flyback converter with an integrated 2.5A, 60V NPN transistor. The DC1643A is designed for 5V output from a 10V to 28V DC input. The output current capability depends on the input voltage, proper cooling, and the switch voltage stress. The output current is up to 1.4A when the input is higher than 10V, and 2A when the input is higher than 20V but less than 28V. The output current should not be higher than 2.4A for safe operation.