1

LT1304/LT1304-3.3/LT1304-5

Micropower

DC/DC Converters with

Low-Battery Detector

Active in Shutdown

The LT

ideal for use in small, low voltage, battery-operated sys-

tems. The devices operate from a wide input supply range

of 1.5V to 8V. The LT1304-3.3 and LT1304-5 generate

regulated outputs of 3.3V and 5V and the adjustable

LT1304 can deliver output voltages up to 25V. Quiescent

current, 120

µA in active mode, decreases to just 10µA in

shutdown with the low-battery detector still active. Peak

switch current, internally set at 1A, can be reduced by

high speed operation of the LT1304 allows the use of

small, surface-mountable inductors and capacitors. The

LT1304 is available in an 8-lead SO package.

, LTC and LT are registered trademarks of Linear Technology Corporation.

s

2-, 3-, or 4-Cell to 5V or 3.3V Step-Up

s

Portable Instruments

s

Bar Code Scanners

s

Palmtop Computers

s

Diagnostic Medical Instrumentation

s

Personal Data Communicators/Computers

s

5V at 200mA from Two Cells

s

10

µA Quiescent Current in Shutdown

s

s

Low-Battery Detector Active in Shutdown

s

s

120

µA Quiescent Current in Active Mode

s

Switching Frequency Up to 300kHz

s

Programmable Peak Current with One Resistor

s

8-Lead SO Package

FEATURES

Efficiency

LOAD CURRENT (mA)

40

50

60

70

80

90

1304 TA02

0.1

1

10

500

100

SW

SHDN

GND

SENSE

LBI

34

8

2

5

7

6

1

LBO

LT1304-5

+

+

100k

100

µF

NC

*

**

604k

100

µF

2 CELLS

499k

22

µH*

D1**

5V

200mA

LBO

LOW WHEN

SUMIDA CD54-220

1N5817

1304 TA01

SHUTDOWN

2-Cell to 5V Step-Up Converter with Low-Battery Detect