LM2733

0.6/1.6 MHz Boost Converters With 40V Internal FET

Switch in SOT-23

General Description

The LM2733 switching regulators are current-mode boost

converters operating fixed frequency of 1.6 MHz (“X” option)

and 600 kHz (“Y” option).

The use of SOT-23 package, made possible by the minimal

power loss of the internal 1A switch, and use of small induc-

tors and capacitors result in the industry’s highest power

density. The 40V internal switch makes these solutions per-

fect for boosting to voltages of 16V or greater.

These parts have a logic-level shutdown pin that can be

used to reduce quiescent current and extend battery life.

Protection is provided through cycle-by-cycle current limiting

and thermal shutdown. Internal compensation simplifies de-

sign and reduces component count.

Switch Frequency

XY

1.6 MHz

0.6 MHz

Features

n

40V DMOS FET switch

n

1.6 MHz (“X”), 0.6 MHz (“Y”) switching frequency

n

Low R

n

Switch current up to 1A

n

Wide input voltage range (2.7V–14V)

n

n

5-Lead SOT-23 package

n

Uses tiny capacitors and inductors

n

Cycle-by-cycle current limiting

n

Internally compensated

Applications

n

White LED Current Source

n

PDA’s and Palm-Top Computers

n

Digital Cameras

n

Portable Phones and Games

n

Local Boost Regulator

Typical Application Circuit

20055424

20055457

20055401

20055458

February 2003

© 2003 National Semiconductor Corporation

DS200554

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