Linear Technology has introduced a new single-chip flyback regulator in TSOT-23 package, which greatly simplifies the design of isolated DC-DC converters.
By sampling the isolated output voltage directly from the primary-side flyback waveform, the LT8303 does not require the opto-isolator LT1431 or the third winding to adjust. The LT8303 operates over an input voltage range of 5.5V to 100V, has an integrated DMOS power switch of 0.45A / 150V, and provides output power up to 5W, making it ideal for a variety of telecommunications, data communications, automotive, industrial, and medical applications. industry. And military applications.
The output voltage is set by only an external resistor and transformer turns ratio. Several off-the-shelf transformers listed in the data sheet can be used for a variety of applications. LT8303 works in boundary mode, which is a variable frequency current mode control switching scheme, which usually results in ± 5% output voltage regulation across the entire line, load, and temperature range. Compared with the equivalent continuous conduction mode design, the boundary mode can use a smaller transformer. The use of high integration and low ripple burst mode operation provides easy-to-use, low component count and efficient application solutions for isolated power delivery.
Other features include output short-circuit protection, 70µA no-load quiescent current, internal loop compensation, accurate enable, and undervoltage lockout with hysteresis.
The company said that the extended and industrial versions have an operating temperature range of -40C to 125C.
