GENERAL DESCRIPTION

DP2281 is a highly integrated current mode PWM

control IC optimized for high performance, low

standby power and cost effective offline flyback

converter applications.

PWM switching frequency at normal operation is

internally fixed and is trimmed to tight range. At no

load or light load condition, the IC operates in

extended burst mode to minimize switching loss,

which can achieve less than 75mW standby.

VDD low startup current and low operating current

contribute to a reliable power on startup and low

standby design with DP2281.

DP2281 offers comprehensive protections

coverage with automatic self-recovery feature

including Cycle-by-Cycle current limiting (OCP),

over load protection (OLP), on-chip Thermal

Shutdown (OTP), VDD over voltage protection

(VDD OVP) and VDD under voltage lockout

(UVLO), etc. Excellent EMI performance is

achieved with frequency shuffling and soft totem

pole gate drive

The tone energy at below 20KHz is minimized in

the design and audio noise is eliminated during

operation.

DP2281 is offered in SOT23-6 package.

FEATURES

■ Less than 75mW Standby Power at Universal

Input

■ Power on Soft Start Reducing MOSFET Vds

Stress

■ Frequency Shuffling for EMI

■ Fixed 65KHz Switching Frequency

■ Internal Synchronized Slope Compensation

■ Low VDD Startup Current and Low Operating

Current

■ Built-in Leading Edge Blanking

■ On-chip Thermal Shutdown

■ Soft Gate Driver for Good EMI Performance

■ Over Load Protection

■ Cycle-by-Cycle Current Limiting

■ VDD Under Voltage Lockout with Hysteresis

(UVLO)

■ VDD OVP & Clamp

APPLICATIONS

Offline AC/DC flyback converter for

■ AC/DC Adapter

■ Open-frame SMPS