UC1103

UNISONIC TECHNOLOGIES CO., LTD UC1103 Preliminary HIGH PRECISION CC/CV PRIMARY SIDE SWITCHING REGULATOR CMOS IC  DESCRIPTION The UTC UC1103 is a primary control unit for switch mode charger and adapter applications. The controlled variable is transferred by an auxiliary winding from the secondary to the primary side. The device integrates PWM controller to enhance the performance of discontinuous conduction mode (DCM) flyback converters. The UTC UC1103 operates in primary-side sensing and regulation. Opto-coupler and TL431 could be eliminated. It also provides off-time modulation to linearly decrease PWM frequency under light-load conditions so that low standby power can be achieved. The UTC UC1103 achieves high precision CV/CC regulation and high power efficiency. It offers comprehensive protection coverage with auto-recovery features including Cycle-by-cycle current limiting, VDD over voltage protection, VDD clamp, OTP, leading edge blanking, VDD under voltage lockout, etc. SOP-8  FEATURES * High voltage startup * ±5% constant voltage regulation at universal AC input * High precision constant current regulation at universal AC input * Primary side control without TL431 and opto-coupler * Programmable CV and CC regulation * Programmable cable compensation in CV mode * Flyback topology in DCM operation * Frequency hopping to reduce system EMI  ORDERING INFORMATION * Driver MOSFET switch * Built-in leading edge blanking * Built-in primary winding inductance compens...