Description
L6668 is a current-mode primary controller IC, designed to build single-ended converters.
The IC drives the system at fixed frequency at heavy load and an improved Standby function causes a smooth frequency reduction as the load is progressively reduced. At very light load the device enters a special operating mode (burst-mode with fixed, externally programmed peak current) that, in addition to the on-board high-voltage start-up and the very low quiescent current, helps keep low the consumption from the mains and be compliant with energy saving regulations. To allow meeting compliance with these standards in power-factor-corrected systems too, an interface with the PFC controller is provided that enables to turn off the pre-regulator when the load level falls below a threshold.

General Features
■ MULTIPOWER BCD TECHNOLOGY
■ LOAD-DEPENDENT CURRENT-MODE CONTROL: FIXED-FREQUENCY (HEAVY LOAD), FREQUENCY FOLDBACK (LIGHT LOAD), BURST-MODE (NO-LOAD)
■ ON-BOARD HIGH-VOLTAGE START-UP
■ IMPROVED STANDBY FUNCTION
■ LOW QUIESCENT CURRENT (< 2 mA)
■ SLOPE COMPENSATION
■ PULSE-BY-PULSE & HICCUP-MODE OCP
■ INTERFACE WITH PFC CONTROLLER
■ DISABLE FUNCTION (ON/OFF CONTROL)
■ LATCHED DISABLE FOR OVP/OTP FUNCTION
■ PROGRAMMABLE SOFT-START
■ 2% PRECISION REFERENCE VOLTAGE EXTERNALLY AVAILABLE
■ ±800 mA TOTEM POLE GATE DRIVER WITH INTERNAL CLAMP AND UVLO PULL-DOWN
■ BLUE ANGEL, ENERGY STAR, EU CODE OF CONDUCT COMPLIANT
■ SO16 PACKAGE ECOPACK®

APPLICATIONS
■ HI-END AC-DC ADAPTERS/CHARGERS FOR NOTEBOOKS.
■ LCD/CRT MONITORS, LCD/CRT TV
■ DIGITAL CONSUMER