Linear Tech’s LT8304 samples the isolated output voltage directly from the primary-side flyback waveform, eliminating the need for an optoisolator or third winding for regulation.
Linear Technology has released a monolithic flyback regulator that operates over an input voltage range of 3V to 100V and delivers up to 24W of isolated output power. Since the LT8304 samples the isolated output voltage directly from the primary-side flyback waveform, there is no need for an optoisolator or third winding for regulation, simplifying the design of isolated DC/DC converters, noted the company.
The LT8304 integrates a 2A, 150V DMOS power switch. Output voltage is programmed with two external resistors and a third optional temperature-compensation resistor. The regulator operates in boundary mode, which is a variable-frequency, current-mode control switching scheme, typically resulting in ±5% output voltage regulation over the full line, load and temperature range. Boundary mode also enables the use of a smaller transformer compared to equivalent continuous conduction-mode designs.
Housed in a thermally enhanced SO-8 package, the LT8304 comes in extended and industrial versions operating over a junction temperature range of -40°C to 125°C. Prices start at $3.55 in lots of 1,000 units.