LT8303

1

8303f

For more information www.linear.com/LT8303

Typical applicaTion

FeaTures

DescripTion

Flyback Converter with

150V/450mA Switch

The LT®8303 is a micropower high voltage isolated flyback

converter. By sampling the isolated output voltage directly

from the primary-side flyback waveform, the part requires

nothirdwindingoropto-isolatorforregulation.Theoutput

voltage is programmed with a single external resistor.

Internalcompensationandsoft-startfurtherreduceexternal

component count. Boundary mode operation provides a

small magnetic solution with excellent load regulation.

LowrippleBurstModeoperationmaintainshighefficiency

at light load while minimizing the output voltage ripple.

A 450mA, 150V DMOS power switch is integrated along

withallhighvoltagecircuitryandcontrollogicintoa5-lead

ThinSOT™ package.

The LT8303 operates from an input voltages range of

5.5V to 100V and can deliver up to 5W of isolated output

power.Thehighlevelofintegrationandtheuseofboundary

and low ripple burst modes result in a simple to use, low

component count, and high efficiency application solution

for isolated power delivery.

L

, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks

and ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the

property of their respective owners. Protected by U.S. Patents, including 5438499, 7463497,

and 7471522.

applicaTions

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5.5V to 100V Input Voltage Range

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450mA, 150V Internal DMOS Power Switch

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Up to 5W of Output Power

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Low Quiescent Current:

70µA in Sleep Mode

280µA in Active Mode

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Boundary Mode Operation at Heavy Load

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Minimum Load <0.5% (Typ) of Full Output

n

n

No Transformer Third Winding or Opto-Isolator

Required for Regulation

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Accurate EN/UVLO Threshold and Hysteresis

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Internal Compensation and Soft-Start

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5-Lead TSOT-23 Package

n

Isolated Telecom, Datacom, Automotive, Industrial,

and Medical Power Supplies

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Isolated Auxiliary/Housekeeping Power Supplies

Efficiency vs Load Current

LOAD CURRENT (mA)

0 100 200 300 400 500 600 700 800 900

40

50

60

70

80

90

100

8303 TA01b

LT8303

T1

6:1

SW

150µH

4.2µH

EN/UVLO

4.7µF

6V TO 80V

5V

GND

316k

•

•

100µF

8303 TA01a