Varistor Products

70

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LA Varistor Series

Line Voltage Operation, Radial Lead

Power Dissipation Ratings

Should transients occur in rapid succession, the average power dissipation

is 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.The

operating values of a MOV need to be derated at high temperatures as

shown in Figure 1. Because varistors only dissipate a relatively small

amount of average power they are not suitable for repetitive applications

that involve substantial amounts of average power dissipation.

V660LA10

10

660L

660

850

70

2500

940

1210

1820

25

70

V660LA50A

14

660L50

660

850

140

4500

940

1210

1820

50

200

V660LA100B

20

660L100

660

850

250

6500

940

1100

1650

100

400

V1000LA80A

14

1000L80

1000

1200

220

4500

1425

1800

2700

50

130

V1000LA160B

20

1000L160

1000

1200

360

6500

1425

1600

2420

100

250

NOTE: Average power dissipation of transients not to exceed 0.25W, 0.4W, 0.6W or 1W for model sizes 7mm, 10mm, 14mm and 20mm, respectively.

PART

NUMBER

MODEL

SIZE

DISC

DIA.

(mm)

DEVICE

MODEL

NUMBER

BRAND-

ING

CONTINUOUS

TRANSIENT

VARISTOR VOLT-

AGE AT 1mA DC

TEST CURRENT

MAXIMUM

CLAMPING

VOLTAGE

8 x 20

µs

TYPICAL

CAPACI-

TANCE

f = 1MHz

ENERGY

10 x 1000

µs

PEAK

CURRENT

8 x 20

µs

MIN

MAX

C

(V)

(V)

(J)

(A)

(V)

(V)

(A)

(pF)

100

90

80

70

60

50

40

30

20

10

0

-55

50

60

70

80

90

100

110

120

130

140 150

FIGURE 1. CURRENT, ENERGY AND POWER DERATING

CURVE

FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM

100

90

50

10

T

TIME

T = Time From 10% to 90% of Peak

Example: For an 8/20

µs Current Waveform:

8

20