©On-Bright Electronics

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OB_DOC_DS_5800

OB2358

Current Mode PWM Power Switch

Freq Shuffling

GENERAL DESCRIPTION

OB2358 combines a dedicated current mode PWM

controller with a high voltage power MOSFET. It

is optimized for high performance, low standby

power, and cost effective off-line flyback converter

applications in sub 27W range.

OB2358 offers complete protection coverage with

automatic self-recovery feature including Cycle-by-

Cycle current limiting (OCP), over load protection

(OLP), VDD over voltage clamp and under voltage

lockout (UVLO).

Excellent EMI performance is

achieved with On-Bright proprietary frequency

shuffling technique together with soft switching

control at the totem pole gate drive output.

The tone energy at below 20KHZ is minimized in the

design and audio noise is eliminated during operation.

OB2358 is offered in DIP8 package.

FEATURES

■

Power on Soft Start Reducing MOSFET Vds

Stress

■

Frequency shuffling for EMI

■

Extended Burst Mode Control For Improved

Efficiency and Minimum Standby Power Design

■

Audio Noise Free Operation

■

Fixed 50KHZ Switching Frequency

■

Internal Synchronized Slope Compensation

■

Low VDD Startup Current and Low Operating

Current

■

Leading Edge Blanking on Current Sense Input

■

Good Protection Coverage With Auto Self-

Recovery

o

VDD Over Voltage Clamp and Under Voltage

Lockout with Hysteresis (UVLO)

o

On-Bright Proprietary Line Input Compensated

Cycle-by-Cycle Over-current Threshold Setting

For Constant Output Power Limiting Over

Universal Input Voltage Range.

o

Overload Protection (OLP).

o

Over voltage Protection(OVP)

APPLICATIONS

Offline AC/DC flyback converter for

■

AC/DC adaptor

■

PDA power supplies

■

Digital Cameras and Camcorder Adaptor

■

VCR, SVR, STB, DVD&DVCD Player SMPS

■

Set-Top Box Power

■

Auxiliary Power Supply for PC and Server

■

Open-frame SMPS

TYPICAL APPLICATION

Output Power Table

230VAC±15%

85-265VAC

Product

Open Frame

1

Open Frame

1

OB2358

27W

16W

Notes:

1.

Maximum practical continuous power in an open frame design with sufficient drain pattern as a heat sink, at 50

ambient.

℃

406442781

On-Bright Confidential to Microbridge