1

© 2009 Littelfuse, Inc.

Specifications are subject to change without notice.

Surface Mount Fuses

438 Series

Ceramic Fuse > 438 Series

Please refer to www.littelfuse.com/series/438.html for current information.

438 Series – 0603 Fast-Acting Fuse

Description

The 438 Series is a 100% Lead-free, RoHS compliant and

Halogen-free fuse series designed specifically to provide

over-current protection to circuits that operate under high

working ambient temperature up to 150ºC.

The general design ensures excellent temperature stability

and performance reliability.

The high I²t values which is typical in the Littelfuse

Ceramic Fuse family ensure high inrush current withstand

capability.

Agency Approvals

AGENCY

AGENCY FILE NUMBER

AMPERE RANGE

E10480

0.250A – 6A

LR29862

0.250A – 6A

Features

Electrical Characteristics for Series

• OperatingTemperature

from -55ºC to +150ºC

• 100%Lead-free,RoHS

compliant and Halogen-

free

• Suitableforbothleaded

and lead-free reflow /

wave soldering

% of Ampere

Rating

Ampere Rating

Opening Time at 25ºC

100%

0.250A – 6A

4 Hours, Minimum

250%

0.250A – 6A

5 Seconds, Maximum

Applications

Ampere

Rating

(A)

Amp

Code

Max.

Voltage

Rating (V)

Interrupting Rating

Nominal

Resistance

Nominal

Nominal Voltage

Drop At Rated

Nominal Power

Dissipation At

Rated Current (W)

Agency Approvals

0.25

.250

63

50A @ 63VDC

50A @ 32VAC

2.024

0.0017

0.550

0.138

x

x

0.375

.375

63

1.247

0.0041

0.488

0.183

x

x

0.5

.500

63

0.829

0.0100

0.486

0.243

x

x

0.75

.750

63

0.466

0.0281

0.378

0.284

x

x

1

001.

63

0.310

0.0593

0.351

0.351

x

x

1.25

1.25

63

0.200

0.0510

0.365

0.456

x

x

1.5

01.5

63

0.174

0.0902

0.368

0.552

x

x

1.75

1.75

63

0.125

0.1440

0.360

0.540

x

x

2

002.

32

50A @ 32VDC/12VAC

0.051

0.1490

0.107

0.214

x

x

2.5

02.5

32

0.0324

0.1977

0.095

0.238

x

x

3

003.

32

0.0252

0.2922

0.093

0.279

x

x

3.5

03.5

32

0.0203

0.4752

0.082

0.287

x

x

4

004.

32

0.0169

0.6920

0.079

0.316

x

x

5

005.

32

0.0113

0.7398

0.074

0.370

x

x

6

006.

24

50A @ 24VDC/12VAC

0.0087

1.3838

0.072

0.432

x

x

Electrical Specifications by Item

Notes:

1. AC Interrupting Rating tested at rated voltage with unity power factor. DC Interrupting

Rating tested at rated voltage with time constant < 0.8 msec.

2. Nominal Resistance measured with < 10% rated current.

3. Nominal Melting I²t measured at 1 msec. opening time.

4. Nominal Voltage Drop measured at rated current after temperature has stabilized.

• HandheldElectronics

• LCDDisplays

• BatteryPacks

• HardDiskDrives

• SDMemoryCards

• AutomotiveElectronics

Devices designed to carry rated current for 4 hours minimum. It is recommended that

devices be operated continuously at no more than 80% rated current. See “Temperature

Rerating Curve”for additional rerating information.

Devices designed to be mounted with marking code facing up.

Revised: February 15, 2012