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Varistor Products

2

Axial Lead

MA Varistor Series

Power Dissipation Ratings

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 specifi-

cations 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 in Figure 1. 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.

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

1.00

100

100

229

243

270

270

311

297

460

440

17

17

V330MA2A

V330MA5B

330

331

188

200

257

274

1.00

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

740

700

11

11

NOTE: Average power dissipation of transients not to exceed 200mW.

PART

NUMBER

BRAND

CONTINUOUS

TRANSIENT

VARISTOR VOLTAGE AT

1mA DC TEST

CURRENT

MAX CLAMPING

VOLTAGE

(8/20µs)

TYPICAL

CAPACI-

TANCE

ENERGY

(10/1000µs)

PEAK

CURRENT

(8/20µs)

MIN

MAX

f = 1MHz

(V)

(V)

(J)

(A)

(V)

(V)

(V)

(V)

(pF)

FIGURE 1. CURRENT, ENERGY AND POWER DERATING

CURVE

100

90

80

70

60

50

40

30

20

10

0

-55

50

60

70

80

90

100 110 120 130 140 150