SF5580
HV-mWTM、η-BalanceTM PWM Controller Fixed 65KHz Fsw
FEATURES
GENERAL DESCRIPTION
◆ Proprietary HV-mWTM to Achieve Less than
SF5580 is a high performance, highly integrated
current mode PWM controller for medium to large
offline flyback power converter applications.
50mW Standby Power
◆ Proprietary η-BalanceTM Control to Boost
Light Load Efficiency
In SF5580, PWM switching frequency with shuffling is
fixed to 65KHz and is trimmed to tight range. When
the output power demands decrease, the IC
decreases switching frequency based on the
◆ Proprietary “Zero OCP/OPP Recovery Gap”
Control
◆ Latch Plug-off Protection with External
Triggering
◆ Fixed 65KHz Switching Frequency
◆ Built-in Soft Start Function
◆ Pin Floating Protection
proprietaryη-BalanceTM control to boost power
conversion efficiency at the light load. SF5580 also
integrates proprietary HV-mWTM technology to
achieve less than 50mW standby power.
SF5580 can achieve “Zero OCP/OPP Recovery
Gap” using SiFirst’s proprietary control algorithm.
SF5580 also has built in proprietary “Audio Noise
Free OCP Compensation”, which can achieve
constant power limiting and can achieve audio noise
operation at heavy loading when line input is around
90VAC.
SF5580 integrates functions and protections of Under
Voltage Lockout (UVLO), VCC Over Voltage
Protection (OVP), Cycle-by-cycle Current Limiting
(OCP), External Programmable Over Temperature
Protection (OTP), Pin Floating Protection, Over Load
Protection (OLP), Soft Start, Gate Clamping, VCC
Clamping, etc.
◆ Frequency Reduction and Burst Mode Control
for Energy Saving
◆ Current Mode Control
◆ Built-in Frequency Shuffling
◆ Built-in Synchronous Slope Compensation
◆ Cycle-by-Cycle Current Limiting
◆ Leading Edge Blanking (LEB)
◆ Constant Power Limiting
◆ Audio Noise Free Operation
◆ VDD UVLO, OVP & Clamp
APPLICATIONS
Offline AC/DC Flyback Converter for
◆ AC/DC Adaptors
◆ Open-frame SMPS
◆ Print Power, Scanners, and Motor Drivers
In SF5580, the OTP, VDD OVP, and RT-pin triggered
protections are Latch Plug-off protection. The other
protection functions are auto-recovery mode
protection.
SF5580 is available in SOP8 and DIP8 packages.
TYPICAL APPLICATION
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SiFirst_DS_5580_V1.1