V18MLA1210H Datasheet, PDF (4/11 Pages) Littelfuse – ML Varistor Series

Surface Mount Varistors
Multilayer Transient Voltage Surge Suppressors
RoHS _{ML Varistor Series}
Temperature De-rating
When transients occur in rapid succession, the average power dissipa-
tion 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. For applications exceeding 125^oC ambient temperature, the peak
surge current and energy ratings must be derated as shown in Figure 1.
100
80
60
40
20
0
-55
50 60 70 80 90 100 110 120 130 140 150
AMBIENTTEMPERATURE ( ^oC)
FIGURE 1. PEAK CURRENT AND ENERGY
DERATING CURVE
100
50
0
t
O₁
t₁
TIME
t₂
FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM
FOR CLAMPING VOLTAGE
O₁ = VIRTUAL ORIGIN OF WAVE
t = TIME FROM 10% TO 90% OF PEAK
t₁ = VIRTUAL FRONT TIME = 1.25 x t
t₂ = VIRTUALTIME TO HALFVALUE
(IMPULSE DURATION)
EXAMPLE:
FOR AN 8/20µs CURRENT WAVEFORM
8µs = t₁ = VIRTUAL FRONT TIME
20µs = t₂ = VIRTUALTIME TO
3
HALF VALUE
MLA0402 Limit VI Curves
100
10
V18MLA0402
V14MLA0402
V9MLA0402
V5.5MLA0402
1
0.000001 0.00001 0.0001 0.001
0.01
0.1
1
10
100
Current (A)
FIGURE 3. LIMIT V-I CHARACTERISTIC FOR V5.5MLA0402 TO V18MLA0402
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