Description
The highly integrated FSBH-series consists of an integrated current-mode Pulse Width Modulator (PWM) and an avalanche-rugged 700V SenseFET. It is specifically designed for high-performance offline Switched-Mode Power Supplies (SMPS) with minimal external components.
The integrated PWM controller features include a proprietary green-mode function that provides off-time modulation to linearly decrease the switching frequency at light-load conditions to minimize standby power consumption. To avoid acoustic-noise problems, the minimum PWM frequency is set above 18kHz. This green-mode function enables the power supply to meet
international power conservation requirements.  The PWM controller is manufactured using the BiCMOS process to further reduce power consumption. The FSBH-series turns off some internal circuits to improve power saving when VFBis lower than 1.6V, which allows an operating current of only 2.5mA.

Features
Brownout Protection with Hysteresis
Built-In 5ms Soft-Start Function
Internal Avalanche-Rugged 700V SenseFET
Low Acoustic Noise During Light-Load Operation
High-Voltage Startup
Linearly Decreasing PWM Frequency to 18KHz
Peak-Current-Mode Control
Cycle-by-Cycle Current Limiting
Leading-Edge Blanking (LEB)
Synchronized Slope Compensation
Internal Open-Loop Protection
VDDUnder-Voltage Lockout (UVLO)
VDDOver-Voltage Protection (OVP)
Internal Auto-Restart Circuit (OVP, OTP)
Constant Power Limit (Full AC Input Range)
Internal OTP Sensor with Hysteresis

Applications
General-purpose switched-mode power supplies and flyback power converters, including:
Auxiliary Power Supply for PC and Server
SMPS for VCR, SVR, STB, DVD & DVCD Player, Printer, Facsimile, and Scanner
Adapter for Camcorder