SiFirst SF1565DP
SF1565 is a high performance, highly integrated current mode PWM controller for medium to large offline flyback converter applications. The IC also integrates Constant Power Limiting block to achieve constant output power limit from 90VAC to 264VAC.FEATURES
● Built-in Soft Start Function● Very Low Startup Current
● Frequency Reduction and Burst Mode Control for Energy Saving
● Built-in Frequency Shuffling
● Programmable Switching Frequency
● Built-in Synchronous Slope Compensation
● Cycle-by-Cycle Current Limiting
● Pins Floating Protection
● High Voltage CMOS Process with Excellent ESD Protection
● Current Mode Control
● Built-in Leading Edge Blanking (LEB)
● Constant Power Limiting
● Audio Noise Free Operation
● VDD OVP & Clamp
● VDD Under Voltage Lockout (UVLO)
GENERAL DESCRIPTION
In SF1565, the PWM switching is internally trimmed to tight range. To improve EMI performance, the IC integrates frequency shuffling function to reduce conduction EMI emission of a power supply. Under light load conditions, a green mode function can continuously decrease the switching frequency. Under zero-load conditions, the power supply enters into burst mode and provides excellent efficiency without audio noise generated. This green mode function enables power supplies to meet international power conservation requirements.