183
Varistor Products
Revision: January 9, 2009
©2008 Littelfuse, Inc. MA Varistor Series
Axial Lead / Application Specific Varistors > MA Series
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ma.html for current information.
MA Series
Description
The MA Series of transient surge suppressors are axial
lead Metal Oxide Varistors (MOVs) for use in a wide
variety of board level industrial and commercial electronic
equipment. They are intended to protect components and
signal/data lines from low energy transients where the
small axial lead package is required.
The MA Series is offered with standard ('S' suffix) or
tightened ('B' suffix) clamping voltage.
See MA Series Device Ratings and Specifications Table for
part number and brand information.
Features
t NNEJBNFUFS
disc size
t 4NBMMBYJBMMFBE
package
t 8JEFPQFSBUJOHWPMUBHF
range:
VM(AC)RMS 9V to 264V
VM(DC) 13V to 365V
t "WBJMBCMFJOUBQFBOE
reel or bulk packaging
t /PEFSBUJOHVQUP
85ºC ambient
t /FXCMBDLFQPYZPGGFST
improved performance
for high temperature
Lead-free wave
soldering process.
Absolute Maximum Ratings
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.
Continuous MA Series Units
Steady State Applied Voltage:
AC Voltage Range (VM(AC)RMS) 9 to 264 V
DC Voltage Range (VM(DC)) 13 to 365 V
Transient:
Peak Pulse Current (ITM)
For 8/20μs Current Wave(See Figure 2) 40 to 100 A
Single-Pulse Energy Range
For 2ms Current Square Wave (WTM) 0.06 to 1.7 J
Operating Ambient Temperature Range (TA) -55 to +85 °C
Storage Temperature Range (TSTG) -55 to +125 °C
Temperature Coefficient (αV) of Clamping Voltage (VC) at Specified Test Current <0.01 %/°C
Hi-Pot Encapsulation (COATING Isolation Voltage Capability)
Dielectric must withstand indicated DC voltage for one minute per MIL-STD 202, Method 301) 1000 V
COATING Insulation Resistance 1000 MΩ
t'PSSBUJOHTPGJOEJWJEVBMNFNCFSTPGBTFSJFTTFF%FWJDF3BUJOHTBOE4QFDJmDBUJPOTDIBSU
MA Varistor Series
RoHS
Agency Approvals
Agency Agency File Number
None
184
Varistor Products
©2008 Littelfuse, Inc.
Revision: January 9, 2009
MA Varistor Series
Axial Lead / Application Specific Varistors > MA Series
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ma.html for current information.
MA Series Ratings & Specifications
Part
Number
Brand
(mm)
Maximum Rating (85°C) Specifications (25°C)
Continuous Transient
Varistor Voltage at 1mA
DC Test Current
Max Clamping
Volt VC at 2.0A
(8/20μs)
Typical
Capacitance
VRMS VDC
Energy
(10/1000μs)
Peak
Current
(8/20μs)
VM(AC) VM(DC) WTM I
TM Min VN(DC) Max VC f = 1MHz
(V) (V) (J) (A) (V) (V) (V) (A) (pF)
V18MA1A
V18MA1A
V18MA1A
18A
18B
18C
9
10
10
13
14
14
0.06
0.07
0.06
40
40
40
14
15
15
18
18
18
23
21
21
49
44
49
550
550
550
V22MA1A
V22MA1B
V22MA1S
22A
22B
22S
10
14
14
15
18
18
0.09
0.10
0.09
40
40
40
16
19
19
22
22
22
28
26
26
55
51
55
410
410
410
V27MA1A
V27MA1B
V27MA1S
27A
27B
27S
13
17
17
19
22
22
0.10
0.11
0.10
40
40
40
21
24
24
27
27
27
34
31
31
67
59
67
370
370
370
V33MA1A
V33MA1B
V33MA1S
33A
33B
33S
18
20
20
23
26
26
0.13
0.15
0.14
40
40
40
26
29.5
29.5
33
33
33
40
36.5
36.5
73
67
73
300
300
300
V39MA2A
V39MA2B
V39MA2S
39A
39B
39S
22
25
25
28
31
31
0.16
0.18
0.17
40
40
40
31
35
35
39
39
39
47
43
43
86
79
86
250
250
250
V47MA2A
V47MA2B
V47MA2S
47A
47B
47S
27
30
30
34
38
38
0.19
0.21
0.19
40
40
40
37
42
42
47
47
47
57
52
52
99
90
99
210
210
210
V56MA2A
V56MA2B
V56MA2S
56A
56B
56S
32
35
35
40
45
45
0.23
0.25
0.23
40
40
40
44
50
50
56
56
56
68
62
62
117
108
117
180
180
180
V68MA3A
V68MA3B
V68MA3S
68A
68B
68S
38
40
40
48
56
56
0.26
0.30
0.27
40
40
40
54
61
61
68
68
68
82
75
75
138
127
138
150
150
150
V82MA3A
V82MA3B
V82MA3S
82A
82B
82S
45
50
50
60
66
66
0.33
0.37
0.34
40
40
40
65
73
73
82
82
82
99
91
91
163
150
163
120
120
120
V100MA4A
V100MA4B
V100MA4S
100
101
102
57
60
60
72
81
81
0.40
0.45
0.42
40
40
40
80
90
90
100
100
100
120
110
110
200
185
200
100
100
100
V120MA1A
V120MA2B
V120MA2S
120
121
122
72
75
75
97
101
101
0.40
0.50
0.46
100
100
100
102
108
108
120
120
120
138
132
132
220
205
220
40
40
40
V150MA1A
V150MA2B
150
151
88
92
121
127
0.50
0.60
100
100
127
135
150
150
173
165
255
240
32
32
V180MA1A
V180MA3B
180
181
105
110
144
152
0.60
0.70
100
100
153
162
180
180
207
198
310
290
27
27
V220MA2A
V220MA4B
220
221
132
138
181
191
0.80
0.90
100
100
187
198
220
220
253
242
380
360
21
21
V270MA2A
V270MA4B
270
271
163
171
224
235
0.90
1. 0 0
100
100
229
243
270
270
311
297
460
440
17
17
V330MA2A
V330MA5B
330
331
188
200
257
274
1. 0 0
1. 10
100
100
280
297
330
330
380
363
570
540
14
14
V390MA3A
V390MA6B
390
391
234
242
322
334
1.20
1.30
100
100
331
351
390
390
449
429
670
640
12
12
V430MA3A
V430MA7B
430
431
253
264
349
365
1.50
1.70
100
100
365
387
430
430
495
473
74 0
700
11
11
NOTE: Average power dissipation of transients not to exceed 200mW.
185
Varistor Products
Revision: January 9, 2009
©2008 Littelfuse, Inc. MA Varistor Series
Axial Lead / Application Specific Varistors > MA Series
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ma.html for current information.
MA Series
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.
Power Dissipation Ratings
100
90
80
70
60
50
40
30
20
10
0
-55 50 60 70 80 90 100 110 120 130 140 150
AMBIENT TEMPERATURE ( oC)
PERCENT OF RATED VALUE
100
90
50
10
O
1
T
T
1
T
2
TIME
PERCENT OF PEAK VALUE
Peak Pulse Current Test Waveform
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:
8μs = T1 = Rise Time
20μs = T2 = Decay Time
Repetitive Surge Capability
100
50
20
10
5
2
1
0.5
0.2
0.1
SURGE CURRENT (A)
20 100 1,000 10,000
IMPULSE DURATION (μs)
2
10
102
103
1
104
105
106
INDEFINITE
DISC SIZE 3mm
V120MA1A - V430MA7B
V120MA1A/S - V430MA3A
50
20
10
5
2
1
0.5
0.2
0.1
2
10
102
103
DISC SIZE 3mm
V18MA1A - V100MA4B
1
104
105
INDEFINITE
106
20 100 1,000 10,000
IMPULSE DURATION (μs)
SURGE CURRENT (A)
V18MA - V100MA
NOTE: If pulse ratings are exceeded, a shift of VN(DC) (at specified current) of more than
+/-10% could result. This type of shift, which normally results in a decrease of VN(DC), may
result in the device not meeting the original published specifications, but it does not
prevent the device from continuing to function, and to provide ample protection.
Figure 1 Figure 2
Figure 3 Figure 4
186
Varistor Products
©2008 Littelfuse, Inc.
Revision: January 9, 2009
MA Varistor Series
Axial Lead / Application Specific Varistors > MA Series
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ma.html for current information.
4,000
3,000
2,000
1,000
900
800
700
600
500
400
300
200
100
10-3 10-2 10 -1 10 010 110 210 3
PEAK AMPERES (A)
V430MA7B
V390MA6B
V330MA5B
V270MA4B
V220MA4B
V180MA3B
V150MA2B
V120MA2B
MAXIMUM CLAMPING VOLTAGE
DISC SIZE 3mm
120 TO 430VN(DC) RATING
TA = -55oC TO 85oC
MAXIMUM PEAK VOLTS (V)
V120MA2B - V430MA7B
600
500
400
300
200
100
90
80
70
60
50
40
30
20
MAXIMUM PEAK VOLTS (V)
10-3
PEAK AMPERES (A)
10-2 10-1 10 010 110 210 3
V33MA1B
V27MA1B
V22MA1B
V100MA4B
V82MA3B
V68MA3B
V18MA1B
MAX CLAMPING VOLTAGE
DISC SIZE 3mm
18 TO 100VN(DC) RATING
TA = -55oC TO 85oC
V47MA2B
V56MA2B
V39MA2B
V18MA1B - V100MA4B
Maximum Clamping Voltage
10-2 10-1 10 010 110 2
MAXIMUM PEAK VOLTS (V)
PEAK AMPERES (A)
MAX CLAMPING VOLTAGE
DISC SIZE 3mm
120 TO 430VN(DC) RATING
TA = -55oC TO 85oC
4,000
2,000
1,500
1,000
800
600
400
200
100
V430MA3A
V390MA3A
V330MA2A
V270MA2A
V220MA2A
V180MA1A
V150MA1A
V120MA1A/S
V120MA1A/S - V430MA3A
800
600
400
300
200
150
100
80
60
40
30
20
10-2 10-1 10 010 110 2
MAXIMUM PEAK VOLTS (V)
V100MA4A/S
V82MA3A/S
V68MA3A/S
V56MA2A/S
V39MA2A/S
V33MA1A/S
V27MA1A/S
V22MA1A/S
V18MA1A/S
PEAK AMPERES (A)
MAX CLAMPING VOLTAGE
DISC SIZE 3mm
18 TO 100VN(DC) RATING
TA = -55oC TO 85oC
V47MA2A/S
V18MA1A/S - V100MA4A/S
Figure 5 Figure 6
Figure 7 Figure 8
187
Varistor Products
Revision: January 9, 2009
©2008 Littelfuse, Inc. MA Varistor Series
Axial Lead / Application Specific Varistors > MA Series
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ma.html for current information.
MA Series
Product Dimensions
LL
Hb (diameter)
D
Symbol Inches Millimeters
Min Max Min Max
Øb 0.024 0.026 0.61 0.66
ØD 0.118 0.177 3.0 4.5
H0.177 0.276 4.5 7.0
L1.740 1.220 27.3 31.0
Typical Weight = 0.5g
Operating/Storage
Temperature -40°C to +85°C
Passive Aging +85°C, 1000 hours
+/-10% typical voltage change
Humidity Aging +85°C, 85% RH, 1000 hours
+/-10% typical voltage change
Thermal Shock +85°C to -40°C 5 times
+/-10% typical voltage change
Solvent Resistance MIL–STD–202, Method 215F
Moisture Sensitivity Level 1, J–STD–020C
Lead Material Tin–plated Copper clad steel
Soldering
Characteristics
Solderability per MIL–STD–202,
Method 208E
Insulating Material Cured, flame retardant epoxy polymer
meets UL94V–0 requirements
Device Labeling Marked with LF, voltage and date code
Physical Specifications
Environmental Specifications
Tape and Reel Dimensions
H1 = H2 +/- 0.040”
H1 H2
0.240”+/- 0.040
2.062”+/- 0.059
2.681” max
0.063” max
Conforms to EIA Standard RS-296-E
0.080” max
0.200” +/- 0.02
Part Numbering System
VARISTOR VOLTAGE
(VN at 1mA)
ENERGY/CLAMPING
VOLTAGE VARIANT
SERIES DESIGNATOR
MA: Bulk Pack
MT: Tape and Reel
V XXX MA XX
VARISTOR
Wave Solder Profile
0
50
100
150
200
250
300
00.511.522.533.54
TIME(MINUTES)
TEMPERATURE
(ºC)
Maximum Wave 240C
Lead–free Profile
0
50
100
150
200
250
300
00.511.522.533.54
TIME(MINUTES)
TEMPERATURE
(ºC)
Maximum Wave 260C
Non Lead–free Profile
Figure 9 Figure 10
