OB2367E

GENERAL DESCRIPTION

OB2367E is a highly integrated current mode PWM control IC optimized for high performance, low standby power and cost effective offline flyback converter applications.

At full loading, the IC operates in fixed frequency (65KHz) mode. When the loading goes low, it operates in Green mode with valley switching for high power conversion efficiency. When the load is very small, the IC operates in ‘Extended Burst Mode’ to minimize the standby power loss. As a result, high conversion efficiency can be achieved in the whole loading range.

VCC low startup current and low operating current contribute to a reliable power on startup and low standby design with OB2367E.

OB2367E offers comprehensive protection coverage with auto-recovery including Cycle-by-Cycle current limiting (OCP) and VCC under voltage lockout (UVLO). It also provides the protections with latched shut down including external over temperature protection (OTP), over load protection (OLP), and over voltage protection (OVP).Excellent EMI performance is achieved with On-Bright proprietary frequency shuffling technique.

The tone energy at below 24KHz is minimized in the design and audio noise is eliminated during operation.

OB2367E is offered in SOT23-6 package. 

 

APPLICATIONS

Offline AC/DC flyback converter for

■   General power supply

■   Power Adapter

FEATURES

■   Power on soft start reducing MOSFET Vds stress

■   Multi-Mode Operation

130KHz max frequency mode @ Peak Load

65KHz fix  frequency mode @ Full Load

Valley switching operation @ Green mode

  Burst Mode @ Light Load & 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

o    VCC Under Voltage Lockout with hysteresis (UVLO)    

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

o    VCC Over Voltage Protection (VCC OVP) with latch

o    Over Load Protection (OLP) with latch

o    External (if NTC resistor is connected at RT pin) or internal (if RT pin floating) Over Temperature Protection (OTP) with latch

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

o    Output SCP protection with latch

o    Output diode short protection

 

TYPICAL APPLICATION