DESCRIPTION

· The LT1248 is a power factor controller designed for universal off-line power systems, utilizing fixed high-frequency PWM current averaging for improved efficiency and reduced line current distortion.

· It features a multiplier with a square gain function from the voltage amplifier to maintain low line current distortion and high system stability, especially under light load conditions.

· The controller includes filtering capabilities to reject line switching noise, minimizing instability and line current dead zones with low bias voltage at the current input.

· It supports operation at frequencies up to 300kHz and includes protection features such as peak current limiting and overvoltage protection.

FEATURES

· High power factor across a wide load range with line current averaging.

· Capable of international operation without the need for switches.

· Provides instantaneous overvoltage protection.

· Features a minimal line current dead zone.

· Typical start-up supply current of 250 mA.

· Effective rejection of line switching noise.

· Synchronization capability for coordinated operation.

· Low quiescent current of 9 mA.

· Fast 1.5 A peak current gate driver.

APPLICATIONS

· Ideal for universal power factor corrected power supplies.

· Suitable for use in preregulators up to 1500W.