No-Opto flyback regulator operates at 150°C

The H-grade versions of the monolithic flyback regulator, the LT8304/-1, from Linear Technology operates for junction temperatures ranging from -40°C to 150°C. By sampling the isolated output voltage directly from the primary-side flyback waveform, the part requires no opto-coupler or third winding for regulation.

The LT8304 operates over input voltages ranging from 3V to 100V, has a 2A/150V integrated DMOS power switch. The device delivers up to 24W of output power, which makes it well suited to a variety of automotive, industrial, medical and military applications. The LT8304-1 version is tailored for high output voltages up to 1kV.

The devices operate in boundary mode, which is said to result in ±5% output voltage regulation over the full line, load and temperature range. Boundary mode enables the use of a smaller transformer compared to equivalent continuous conduction mode designs.

Several off-the-shelf transformers can be used for numerous applications. The high level of integration and the use of low ripple Burst Mode operation result in a simple to use, low component count and high efficiency solution for isolated power delivery.

Additional features include output short-circuit protection, 116µA no load operating quiescent current, accurate enable and under voltage lockout with hysteresis, internal soft-start and loop compensation, along with output diode temperature compensation.

Peggy Lee