ANALOG DEVICES MAX668EUB+

The MAX668EUB+ is a constant-frequency, pulse-width modulating (PWM), current-mode DC-DC Controller is designed for a wide range of DC-DC conversion applications including step-up, SEPIC, flyback and isolated output configurations. Power levels of 20W or more can be controlled with conversion efficiencies of over 90%. The 1.8 to 28V input voltage range supports a wide range of battery and AC-powered inputs. An advanced BiCMOS design features low operating current (220μA), adjustable operating frequency (100 to 500kHz), soft-start and a SYNC input allowing the MAX668 oscillator to be locked to an external clock. DC-DC conversion efficiency is optimized with a low 100mV current-sense voltage as well as with Maxims proprietary Idle Mode™ control scheme. The controller operates in PWM mode at medium and heavy loads for lowest noise and optimum efficiency, then pulses only as needed (with reduced inductor current) to reduce operating current and maximize efficiency under light loads.