OB2362

GENERAL DESCRIPTION

OB2362is a high performance flyback adaptive multi-mode(CCM/QR) PWM controller, optimized to achieve high efficiency and low standby powerwith effective system cost.

At heavy load, the IC operates in fixed frequency(65kHz) CCM mode in the low line input voltage. At medium load, it operates in QR mode , at light load ,it operates in green mode with valley skip, and at no load the IC operates in extended ‘burst mode’ to minimize switching loss. Lower standby power and higher conversion efficiency is thus achieved.

VCC low startup current and low operating current contribute to a reliable power on startup and low standby design with OB2362.

OB2362 offers comprehensive protection coverage with auto-recovery including Cycle-by-Cycle current limiting (OCP), over load protection (OLP), and VCC under voltage lockout (UVLO). It also provides the protections with latched shut down including over temperature protection (OTP), and over voltage protection (OVP).Excellent EMI performance is achieved with On-Bright proprietary frequency shuffling technique.

The tone energy at below 25KHz is minimized in the design and audio noise is eliminated during operation.

OB2362 is offered in SOT23-6 package.

FEATURES

■Power on soft start reducing MOSFET Vds stress

■Multi-Mode Operation

CCM @ Heavy Load and Low Line

Quasi-Resonant operation @ Medium Load

Green mode with valley skip @ Light Load

Burst Mode @ No Load

■Frequency shuffling for EMI

■Extended burst mode control for improved efficiency and low standby power design

■Audio noise free operation

■Comprehensive protection coverage

oVCC Under Voltage Lockout with hysteresis (UVLO)

oVCC Over Voltage Protection (VCC OVP)

oCycle-by-cycle over current threshold setting for constant output power limiting over universal input voltage range

oOver Load Protection (OLP) with auto-recovery

oExternal (if NTC resistor is connected at PRT pin)or internal Over Temperature Protection (OTP) with latched shut down

oOutput Over Voltage Protection(Output OVP) with latched shut down, andthe OVP triggered voltage can be adjusted by the resistor connected between auxiliary winding and PRT pin

oOutput diode short protection with auto-recovery

APPLICATIONS

Offline AC/DC flyback converter for

■Power Adapter

■Set-Top Box Power Supplier

■Open-frame SMPS

TYPICAL APPLICATION

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