Linear Technology's LT3573EMSE#TRPBF: A Robust Isolated Flyback Converter

The LT3573EMSE#TRPBF from Linear Technology is a highly integrated and versatile isolated flyback converter that simplifies the design of an isolated DC/DC converter. Designed for versatility, it does not require the use of an opto-isolator, third winding, or signal transformer for feedback, as the device's output voltage is sensed from the primary-side flyback signal. This innovative feature significantly reduces complexity and enhances reliability in a wide range of applications.

With an input voltage range of 3V to 40V, the LT3573EMSE#TRPBF is suitable for a variety of input sources, including automotive batteries, industrial supplies, and more. It is capable of delivering up to several watts of output power, which can be adjusted based on the transformer design and the choice of external components. The integrated 1.25A, 60V NPN power switch contributes to the compactness and efficiency of the overall design.

The device operates in boundary mode, which is a variable frequency current mode control switching scheme, resulting in ±5% typical regulation over the full line, load, and temperature range. This mode of operation provides a good compromise between the efficiency of hard switching converters and the minimal EMI and transient response of phase-shifted converters.

Additional features of the LT3573EMSE#TRPBF include programmable soft-start, which limits inrush current during startup, and an onboard error amplifier for loop compensation and flexibility in choosing output voltage. The device also has under-voltage lockout (UVLO) and thermal shutdown for added protection.

Encased in a compact MSOP-16 package, the LT3573EMSE#TRPBF is designed for space-constrained applications. Its robust construction and high level of integration make it an ideal choice for isolated power supplies in industrial controls, medical equipment, telecommunications, and automotive systems, where reliability and performance are paramount.

Overall, the LT3573EMSE#TRPBF is a testament to Linear Technology's commitment to delivering high-performance power management solutions that streamline the design process while ensuring robust operation in demanding environments.