Littelfuse LR User Manual

LR Series

POLYFUSE® Resettable PTCs

POLYFUSE® Resettable PTCs

Axial Lead Battery Strap Type > LR Series

Description

The new LR Series device provides reliable, noncycling
protection against overcharging and short circuits events
for rechargeable battery cells where resettable protection
is desired.

Features

• RoHS compliant and
lead–free

• Weldable Nickel terminals

• Slim, low profile design

Agency Approvals

AGENCY AGENCY FILE NUMBER

E183209

Applications

• Rechargeable battery cell
protection

• Portable Computers

R50119583

Electrical Characteristics

Maximum Time

d

Current

(A)

To Trip

Time

(Sec.)

Part Number

I

hold

(A)

I
(A)

V

trip

(Vdc)

max

I

(A)

max

P

max.

(W)

15LR190 1.9 3.9 15 100 1.2 9.50 5.00 0.039 0.072 0.102

15LR190S 1.9 3.9 15 100 1.2 9.50 5.00 0.039 0.072 0.102

15LR260 2.6 5.8 15 100 2.5 13.00 5.00 0.020 0.042 0.063

15LR260S 2.6 5.8 15 100 2.5 13.00 5.00 0.020 0.042 0.063

15LR380 3.8 8.3 15 100 2.5 19.00 5.00 0.013 0.026 0.037

20LR450 4.5 8.9 20 100 2.5 22.50 5.00 0.011 0.020 0.028

20LR550 5.5 10.5 20 100 2.8 27.50 5.00 0.009 0.016 0.022

20LR600 6.0 11.7 20 100 2.8 30.00 5.00 0.007 0.014 0.019

20LR730 7.3 14.1 20 100 3.3 30.00 5.00 0.006 0.012 0.015

I

= Hold current: maximum current device will pass without tripping in 20°C still air.

hold

= Trip current: minimum current at which the device will trip in 20°C still air.

I

trip

= Maximum voltage device can withstand without damage at rated current (I max)

V

max

= Maximum fault current device can withstand without damage at rated voltage (V

I

max

= Power dissipated from device when in the tripped state at 20°C still air.

P

d

= Minimum resistance of device in initial (un-soldered) state.

R

min

)

max

= Typical resistance of device in initial (un-soldered) state.

R

typ

= Maximum resistance of device at 20°C measured one hour after tripping or reflow

R

1max

soldering of 260°C for 20 sec.

Caution: Operation beyond the specified rating may result in damage and possible arcing
and flame.

R

(Ω)

min

Resistance

R

typ

(Ω)

• Compact design saves
board space

• Low resistance

• Fast trip time

• Camcorders

Agency

Approvals

R

1max

(Ω)

XX

XX

XX

XX

XX

XX

XX

XX

XX

LR Series

© 2010 Littelfuse, Inc

Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/LR.html for current information.

113

Revised: June 4, 2010

LR Series

POLYFUSE® Resettable PTCs

Axial Lead Battery Strap Type > LR Series

Temperature Rerating

Ambient Operation Temperature

-40°C -20°C 0°C 23°C 40°C 50°C 60°C 70°C 85°C

Part Number Hold Current (A)

15LR190 2.80 2.50 2.30 1.90 1.60 1.50 1.40 1.20 1.00

15LR190S 2.80 2.50 2.30 1.90 1.60 1.50 1.40 1.20 1.00

15LR260 3.80 3.40 3.10 2.60 2.20 2.00 1.90 1.70 1.40

15LR260S 3.80 3.40 3.10 2.60 2.20 2.00 1.90 1.70 1.40

15LR380 5.50 4.90 4.40 3.80 3.30 3.00 2.80 2.50 2.10

20LR450 6.50 5.80 5.30 4.50 3.90 3.60 3.30 2.90 2.50

20LR550 8.00 7.10 6.20 5.50 4.70 4.30 4.00 3.60 3.00

20LR600 8.70 7.80 7.10 6.00 5.20 4.70 4.40 3.90 3.30

20LR730 10.60 9.50 8.60 7.30 6.30 5.70 5.40 4.70 4.00

Average Time Current Curves

1.90 A

2.60 A

3.80 A

4.50 A

5.50 A

6.00 A

10

1

Time in Seconds

0.1

0.01
1 10 100 1000

Current in Amperes

7.30 A

LR

Temperature Rerating Curve

170%

150%

B

A

130%

110 %

90%

70%

50%

Percentage of Rated Current

30%

10%

Line/Part Number:

A

15LR190

• 15LR260

15LR190S

• 15LR260S

15LR260

• 15LR450

-40 -30 -20 -10 0 10 20 30 40 50607080

B

15LR380
15LR550
15LR600
20LR730

Temperature (°C)

A

B

The average time current curves and Temperature Rerating curve performance is affected
by a number or variables, and these curves provided as guidance only. Customer must
verify the performance in their application.

LR Series

Revised: June 4, 2010

114

© 2010 Littelfuse, Inc.

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

Specifications are subject to change without notice.