Littelfuse RA Series Catalog Page

Varistor Products

Low Profile / Application Specific Varistors > RA Series

RoHS

RA Varistor Series

Agency Approvals

Agency Agency File Number

E320116

LR91788

Description

The RA Series transient surge suppressors are varistors
(MOVs) supplied in a low-profile box that features a precise
seating plane to increase mechanical stability for secure
circuit-board mounting. This feature makes these devices
suitable for industrial applications critical to vibration. Their
construction permits operation up to 125ºC (ambient)
without derating.

The RA Series are available in voltage ratings up to 275V
V

, and energy levels up to 140J. These varistors are

M(AC)RMS

used in automotive, motor-control, telecommunication, and
military applications.

See RA Series Device Ratings and Specifications Table for
part number and brand information.

Features

• Lead–free/RoHS
compliant parts
available (add
suffix "x2749")

• Low profile outline with
precise seating plane

• No derating up to
125ºC ambient

• In-line leads

• Wide operating
voltage range:

V

M(AC)RMS

V

M(DC):

: 4 – 275V

5.5 – 369V

• High energy absorption
capability W

TM

up to 140J

• 3 model sizes available
A8, RA16, and RA22

Absolute Maximum Ratings

• For ratings of individual members of a series, see Device Ratings and Specifications chart

Continuous RA8 Series RA16 Series RA22 Series Units

Steady State Applied Voltage:

AC Voltage Range (V

DC Voltage Range (V

Transients:

Peak Pulse Current (ITM)

For 8/20μs Current Wave (See Figure 2) 100 to 1200 1000 to 4500 2000 to 6500 A

Single Pulse Energy Range (Note 1)

For 10/1000μs Current Wave (W

Operating Ambient Temperature Range (T

Storage Temperature Range (T

Temperature Coefficient (a

Hi-Pot Encapsulation (COATING Isolation Voltage Capability)

(Delectric must withstand indicated DC voltage for one minute per MIL-STD 202, Method 301)

COATING Insulation Resistance 1000 1000 1000 MΩ

CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and
operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not implied.

) -55 to +150 -55 to +150 -55 to +150 ºC

STG

V

) of Clamping Voltage (VC) at Specified Test Current <0.01 <0.01 <0.01 %/ºC

) 4 to 275 10 to 275 4 to 275 V

M(AC)RMS

) 5.5 to 369 14 to 369 18 to 369 V

M(DC)

) 0.4 to 23 3.5 to 75 70 to 160 J

) -55 to +125 -55 to +125 -55 to +125 ºC

A

TM

5000 5000 5000 V

RA Series

©2009 Littelfuse, Inc.

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

193

Revision: November 11, 2009

RA Varistor Series

Varistor Products

Low Profile / Application Specific Varistors > RA Series

RA Series Ratings & Specifications

Maximum Rating (125°C) Specifications (25°C)

Continuous Transient

Part

Number

Brand

Energy

(10/1000μs)

WTM I

V

V

M(DC)

DC

V

RMS

V

M(AC)

Peak
Current
(8/20μs)

TM

Varistor Voltage at 1mA

DC Test Current

Min V

N(DC)

Max V

(mm) (V) (V) (J) (A) (V) (V) (V) (V) (A) (pF)

† RA8 Series

V8RA8 8R 4 5.5 0.4 150 6 8.2 11.2 22 5 3000

V12RA8 12R 6 8 0.6 150 9 12 16 34 5 2500

V18RA8 18R 10 14 0.8 250 14.4 18 21.6 42 5 2000

V22RA8 22R 14

18

(Note 3)

10

(Note 2)

250 18.7 22 26 47 5 1600

V27RA8 27R 17 22 1.0 250 23 27 31.1 57 5 1300

V33RA8 33R 20 26 1.2 250 29.5 33 36.5 68 5 1100

V39RA8 39R 25 31 1.5 250 35 39 43 79 5 900

V47RA8 47R 30 38 1.8 250 42 47 52 92 5 800

V56RA8 56R 35 45 2.3 250 50 56 62 107 5 700

V68RA8 68R 40 56 3.0 250 61 68 75 127 5 600

V82RA8 82R 50 66 4.0 1200 74 82 91 135 10 500

V100RA8 100R 60 81 5.0 1200 90 100 110 165 10 400

V120RA8 120R 75 102 6.0 1200 108 120 132 205 10 300

V150RA8 150R 95 127 8.0 1200 135 150 165 250 10 250

V180RA8 180R 115 153 10.0 1200 162 180 198 295 10 200

V200RA8 200R 130 175 11.0 1200 184 200 228 340 10 180

† V220RA8 220R 140 180 12.0 1200 198 220 242 360 10 160

† V240RA8 240R 150 200 13.0 1200 212 240 268 395 10 150

† V270RA8 270R 175 225 15.0 1200 247 270 303 455 10 130

† V360RA8 360R 230 300 20.0 1200 324 360 396 595 10 100

† V390RA8 390R 250 330 21.0 1200 354 390 429 650 10 90

† V430RA8 430R 275 369 23.0 1200 389 430 473 710 10 80

Max Clamping

at 2.0A

Volt V

C

(8/20μs)

C

I

p

Typical

Capacitance

f = 1MHz

† RA16 Series

V18RA16 18R16 10 14 3.5 1000 14.4 18 21.6 39 10 11000

V22RA16 22R16 14

18 (Note 3)50 (Note

2)

1000 18.7 22 26 43 10 9000

V27RA16 27R16 17 22 5.0 1000 23 27 31.1 53 10 7000

V33RA16 33R16 20 26 6.0 1000 29.5 33 36.5 64 10 6000

V39RA16 39R16 25 31 7.2 1000 35 39 43 76 10 5000

V47RA16 47R16 30 38 8.8 1000 42 47 52 89 10 4500

V56RA16 56R16 35 45 10.0 1000 50 56 62 103 10 3900

V68RA16 68R16 40 56 13.0 1000 61 68 75 123 10 3300

V82RA16 82R16 50 66 15.0 4500 74 82 91 145 50 2500

V100RA16 100R16 60 81 20.0 4500 90 100 110 175 50 2000

V120RA16 120R16 75 102 22.0 4500 108 120 132 205 50 1700

V150RA16 150R16 95 127 30.0 4500 135 150 165 255 50 1400

V180RA16 180R16 115 153 35.0 4500 162 180 198 300 50 1100

RA Varistor Series

194

Revision: November 11, 2009

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

Specifications are subject to change without notice.

©2009 Littelfuse, Inc.

Varistor Products

Low Profile / Application Specific Varistors > RA Series

RA Series Ratings & Specifications

Maximum Rating (125°C) Specifications (25°C)

Continuous Transient

Part

Number

Brand

V

V

RMS

M(AC)

V

DC

V

M(DC)

Energy

(10/1000μs)

WTM I

Peak
Current
(8/20μs)

TM

Varistor Voltage at 1mA

DC Test Current

Min V

N(DC)

Max V

(mm) (V) (V) (J) (A) (V) (V) (V) (V) (A) (pF)

V200RA16 200R16 130 175 38.0 4500 184 200 228 340 50 1000

† V220RA16 220R16 140 180 42.0 4500 198 220 242 360 50 900

† V240RA16 240R16 150 200 45.0 4500 212 240 268 395 50 800

† V270RA16 270R16 175 225 55.0 4500 247 270 303 455 50 700

† V360RA16 360R16 230 300 70.0 4500 324 360 396 595 50 550

† V390RA16 390R16 250 330 72.0 4500 354 390 429 650 50 500

† V430RA16 430R16 275 369 75.0 4500 389 430 473 710 50 450

† RA22 Series

V24RA22 24R22 14

18

(Note 3)

V36RA22 36R22 23 31

100.0

(Note 2)

160.0

(Note 2)

2000 19.2

2000 32

24

(Note 4)

36

(Note 4)

† V200RA22 200R22 130 175 70.0 6500 184 200 228 340 100 1900

† V240RA22 240R22 150 200 80.0 6500 212 240 268 395 100 1600

† V270RA22 270R22 175 225 90.0 6500 247 270 303 455 100 1400

† V390RA22 390R22 250 330 130.0 6500 354 390 429 650 100 1000

† V430RA22 430R22 275 369 140.0 6500 389 430 473 710 100 900

1. Average power dissipation of transients not to exceed 0.25W for RA8 Series, 0.60W for RA16 Series, or 1.0W for RA22 Series.

NOTES:

2. Energy ratings for impulse duration of 30ms minimum to one half of peak current value.

3. Also rated to withstand 24V for 5 minutes.

4. 10mA DC Test Current.
† Under UL File No. E320116 as a recognized component. CSA approved File No. LR91788.

Max Clamping

Volt V

at 2.0A

C

(8/20μs)

C

I

p

Typical

Capacitance

f = 1MHz

26 43 20 18000

40 63 20 12000

Power Dissipation Ratings

100

90

80

70

60

50

40

30

20

PERCENT OF RATED VALUE

10

0

Figure 1

-55 50 60 70 80 90 100 110 120 130 140 150

AMBIENT TEMPERATURE (

Should transients occur in rapid succession, the average power
dissipation required is simply the energy (watt-seconds) per pulse
times the number of pulses per second. The power so developed
must be within the specifications shown on the Device Ratings
and Specifications table for the specific device. Furthermore,
the operating values need to be derated at high temperatures as
shown above. Because varistors can only dissipate a relatively
small amount of average power they are, therefore, not suitable
for repetitive applications that involve substantial amounts of aver­age power dissipation.

©2009 Littelfuse, Inc.

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

o

C)

Revision: November 11, 2009

Peak Pulse Current Test Waveform

100

90

50

10

1

Figure 2

01 = Virtual Origin of Wave
T = Time from 10% to 90% of Peak
T1 = Rise Time = 1.25 x T
T2 = Decay Time

Example - For an 8/20 μs Current Waveform:

195

T

T

1

8μs = T1 = Rise Time
20μs = T2 = Decay Time

TIME

T

2

RA Series

RA Varistor Series