The LT3825 is an isolated switching regulator controller designed for medium power flyback topologies. A typical application is 10W to 60W with input voltage limited onlyby external power path components. A third transformer winding provides output voltage feedback. The LT3825 is a current mode controller that regulates output voltage based on sensing secondary voltage via a transformer winding during flyback. This allows for tight output regulation without the use of an opto-isolator,improving dynamic response and reliability. Synchronous rectification increases converter efficiency and improves output cross regulation in multiple output converters. The LT3825 operates in forced continuous conduction mode which improves cross regulation in multiple winding applications.Switching frequency is user programmable and can be externally synchronized. The part also has load compensation, undervoltage lockout and soft-start circuity.
