OB5269

GENERAL DESCRIPTION

OB5269 is a highly integrated current mode PWM control IC with high voltage start up, optimized for high performance, low standby power consumption and cost effective offline flyback converter applications.

PWM switching frequency at normal operation is internally fixed and is trimmed to a tight range. At no load or light load condition, the IC operates in extended ‘burst mode’ to minimize switching loss. Very low standby power consumption and very high conversion efficiency is thus achieved.

High voltage startup is implemented in OB5269, which features with short startup time and low standby current.

OB5269 offers complete protection coverage with auto-recovery including Cycle-by-Cycle current limiting (OCP), over load protection (OLP), and VDD under voltage lockout (UVLO). It also provides the protections with latched shut down including over temperature protection (OTP), and over voltage (fixed or adjustable) protection (OVP).  Excellent EMI performance is achieved with On-Bright proprietary frequency shuffling technique.

The tone energy at below 22KHZ is minimized to avoid audio noise during operation.

OB5269 is offered in SOP8 package.

 

FEATURES

• High Voltage Startup

• Power on Soft Start Reducing MOSFET Vds Stress

• Frequency shuffling for EMI

• Extended Burst Mode Control For Improved Efficiency and Minimum Standby Power

• Audio Noise Free Operation

• Fixed 65KHZ Switching Frequency

• Comprehensive Protection Coverage

  • VDD Under Voltage Lockout with Hysteresis (UVLO)       

  • Cycle-by-cycle over current protection (OCP)

  • Overload Protection (OLP) with auto-recovery

  • Over Temperature Protection (OTP) with latch shut down

  • VDD Over voltage Protection(OVP) with latch shut down

  • Adjustable OVP through external Zener

      

APPLICATIONS

Offline AC/DC flyback converter for

• Battery Charger

• Power Adaptor

• Open-frame SMPS

   

TYPICAL APPLICATION