High-integrated Green-mode Pwm Controller

This highly integrated PWM Controllers SG6841 series, provides several features to enhance the performance of low power flyback converters. To minimize standby power consumption, the proprietary green-mode function provides off-time modulation to linearly decrease the switching frequency under light-load conditions. This green-mode function assists the power supply to easily meet the power conservation requirement. Due to BiCMOS process, the start-up current and operation current is reduced to 30uA and 3mA, respectively, to improve power conversion efficiency. Large start-up resistance CAN be used for further power saving. Built-in synchronized slope compensation ensures the stability of peak current mode control. A proprietary internal compensation ensures constant output power limit for universal AC input voltage from 90VAC to 264VAC. SG6841 provides many protection functions. Pulse by pulse current limit ensures a constant output current under short circuit. If a short circuit failure or over load happens, the SG6841 will shut off after a continuous high voltage detection on FB pin. The Gate output is clamped at 18V to protect the power MOS from over voltage damage. An external NTC thermistor CAN be applied to sense the ambient temperature for over-temperature protection. The SG6841 series are available in 8-pin DIP and SO packages. By Unkown