LT8303 is a monolithic flyback regulator in a TSOT-23 package that simplifies the design of isolated DC/DC converters. By sampling the isolated output voltage directly from the primary-side flyback waveform, the part requires no opto-isolator, LT1431 or third winding for regulation. by Graham Prophet @ edn-europe.com
The LT8303 operates over a 5.5V to 100V input voltage range, has a 0.45A/150V integrated DMOS power switch and delivers up to 5W, suiting it for a range of telecom, datacom, automotive, industrial, medical and military applications. The output voltage is set with one external resistor and the transformer turns ratio. Several off-the-shelf transformers are identified in the data sheet. The LT8303 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 enables the use of a smaller transformer compared to equivalent continuous conduction mode designs. 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 application solution for isolated power delivery.
100Vin, 5W out regulator uses primary-side control – [Link]