LT3511

1

3511fa

Typical applicaTion

FeaTures

DescripTion

Monolithic High Voltage

Isolated Flyback Converter

tor specifically designed for the isolated flyback topology.

No third winding or opto-isolator is required for regula-

tion as the part senses output voltage directly from the

primary-side flyback waveform. The device integrates a

240mA, 150V power switch, high voltage circuitry, and

control into a high voltage 16-lead MSOP package with

four leads removed.

The LT3511 operates from an input voltage range of 4.5V

to 100V and delivers up to 2.5W of isolated output power.

Two external resistors and the transformer turns ratio

easily set the output voltage. Off-the-shelf transformers

are available for several applications. The high level of

integrationandtheuseofboundarymodeoperationresults

in a simple, clean, tightly regulated application solution to

the traditionally tough problem of isolated power delivery.

Output Load and Line Regulation

48V to 5V Isolated Flyback Converter

applicaTions

n

4.5V to 100V Input Voltage Range

n

Internal 240mA, 150V Power Switch

n

Boundary Mode Operation

n

No Transformer Third Winding or

Opto-Isolator Required for Regulation

n

Improved Primary-Side Winding Feedback

Load Regulation

n

n

BIAS Pin for Internal Bias Supply and Power

Switch Driver

n

No External Start-Up Resistor

n

16-Lead MSOP Package

n

Isolated Telecom Power Supplies

n

Isolated Auxiliary/Housekeeping Power Supplies

n

Isolated Industrial, Automotive and Medical Power

Supplies

L

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

property of their respective owners. Protected by U.S. Patents, including 5438499, 7471522.

EN/UVLO

SW

VC

GND BIAS

LT3511

3511 TA01a

69.8k

16.9k

36V TO 72V

5V

0.3A

4:1

1M

1µF

43.2k

19µH

300µH

22µF

3.3nF

4.7µF

10k

169k

•

•

LOAD CURRENT (mA)

0

4.75

4.85

4.95

5.05

50

100

150

200

3511 TA01b

250

5.15

5.25

4.80

4.90

5.00

5.10

5.20

300