SG5842A Datasheet | Fairchild Semiconductor

SG5842A/SG5842JA - Highly Integrated Green-Mode PWM Controller SG5842A/SG5842JA - Highly Integrated Green-Mode PWM Controller Features - Green-Mode PWM Controller - Low Startup Current: 14µA - Low Operating Current: 4m A - Programmable PWM Frequency with Hopping (SG5842JA) - Peak-Current-Mode Control - Cycle-by-Cycle Current Limiting - Synchronized Slope pensation - Leading-Edge Blanking (LEB) - Constant Output Power Limit - Totem-Pole Output with Soft Driving - VDD Over-Voltage Protection (OVP) - Programmable Over-Temperature Protection (OTP) - Internal Latch Circuit (OTP, OVP) - Internal Open-Loop Protection - VDD Under-Voltage Lockout (UVLO) - GATE Output Maximum Voltage Clamp: 18V Applications General-purpose switch-mode power supplies and flyback power converters, including: - Notebook Power Adapters - Open-Frame SMPS Description The highly integrated SG5842A/JA series of PWM controllers provides several Features to enhance the performance of flyback converters. To minimize standby power consumption, a proprietary green-mode function provides off-time modulation to continuously decrease the switching frequency at light-load conditions. To avoid acoustic-noise problems, the minimum PWM frequency set above 22KHz. This green-mode function enables the power supply to meet international power conservation requirements. To further reduce power consumption, SG5842A/JA is manufactured using the Bi CMOS process. This allows a low startup current, around 14µA, and an operating current of only 4m A. As a result, a large startup resistance can be used. The SG5842A/JA built-in synchronized slope pensation achieves stable peak-current-mode control. SG5842JA integrates a frequency-hopping function that helps reduce EMI emission of a power supply with minimum line filters. SG5842A/JA provides many protection functions. In addition to cycle-by-cycle current limiting, the internal open-loop protection circuit ensures safety should an open-loop or output short-circuit...