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