资 源 简 介
OB2211H is an offline PWM Power switch for lowpower AC/DC charger and adaptor applicaTIons. Itoperates in primary-side sensing and regulaTIon.Consequently, opto-coupler and TL431 could beeliminated. Proprietary Constant Voltage (CV) andConstant Current (CC) control is integrated as shownin the figure below.In CC control, the current and output power setTIngcan be adjusted externally by the sense resistor Rs atCS pin. In CV control, mulTI-mode operations areutilized to achieve high performance and highefficiency. Device operates in fixed frequency modeat large load conditions, frequency reduction mode atlight/medium load and ‘Extended burst mode’ atNo/light load conditions.OB2211H offers power on soft start control andprotection coverage with auto-recovery featuresincluding Cycle-by-Cycle current limiting, VDDclamp and UVLO. Excellent EMI performance isachieved with On-Bright proprietary frequencyshuffling technique together with soft switchingcontrol at the totem pole gate drive output.OB2211H achieves better CC control accuracy andhigher system efficiency through PWM control thanits sibling part OB2211.
