Datasheet

Metal-Oxide Varistors (MOVs)
High Reliability Varistors
QPL
High Reliability Varistors
Description
Littelfuse High Reliability Varistors offer the latest in
increased product performance, and are available for
applications requiring quality and reliability assurance
levels consistent with military or other standards
(MIL-STD-19500, MIL-STD-202). Additionally, Littelfuse
Varistors are inherently radiation hardened compared
to Silicon Diode suppressors as illustrated in Figure 1.
ZA Series
Littelfuse High-Reliability Varistors involve four categories:
1 Qualified Products List (QPL) MIL-R-83530 (4 items presently available)
Agency Approvals
2 Littelfuse High Reliability Series TX Equivalents (29 items presently available)
•QPL
3 Custom Types
Additional Information
Datasheet
Resources
© 2015 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 11/04/15
Samples
Processed to customer-specific requirements
- (SCD) or to Standard Military Flow
Metal-Oxide Varistors (MOVs)
High Reliability Varistors
1) DSSC Qualified Parts List (QPL) MIL-R-83530
This series of varistors are screened and conditioned in accordance with MIL-R-83530. Manufacturing system conforms to
MIL-I-45208; MIL-Q-9858.
Table 1. MIL-R-83530/1 Ratings and Characteristics
Part
Number
M83530/
Nominal
Varistor
Voltage
(V)
Tolerance
(%)
1-2000B
1-2200D
1-4300E
1-5100E
200
220
430
510
-/+10
+10, -5
+5, -10
+5, -10
Voltage Rating
(V)
(RMS)
(DC)
130
150
275
320
175
200
369
420
Energy
Rating (J)
Clamping
Voltage at
100A (V)
50
55
100
120
325
360
680
810
Clamping
Nearest
Capacitance Voltage At
Commercial
at 1MHz (pF) Peak Current
Equivalent
Rating (V)
3800
3200
1800
1500
570
650
1200
1450
V130LA20B
V150LA20B
V275LA40B
V320LA40B
2) Littelfuse High Reliability Series TX Equivalents
Table 2. Available TX Model Types
Model Size
Device
Mark
(See Section
4) Nearest
Commercial
Equivalent
V130LTX2
V130LTX10A
V130LTX20B
7mm
14mm
20mm
130TX
130TX10
130TX20
V130LA2
V130LA10A
V130LA20A
V150LTX2
V150LTX10A
V150LTX20B
7mm
14mm
20mm
150TX
150TX10
150TX20
V150LA2
V150LA10A
V150LA20B
V250LTX4
V250LTX20A
V250LTX40B
7mm
14mm
20mm
250TX
250TX20
250TX40
V250LA4
V250LA20A
V250LA40B
(See Section
4) Nearest
Commercial
Equivalent
TX Model
TX Model
Model Size
Device
Mark
V8ZTX1
V8ZTX2
7mm
10mm
8TX1
8TX2
V8ZA1
V8ZA2
V12ZTX1
V12ZTX2
7mm
10mm
12TX1
12TX2
V12ZA1
V12ZA2
V22ZTX1
V22ZTX3
7mm
14mm
22TX1
22TX3
V22ZA1
V22ZA3
V24ZTX50
20mm
24TX50
V24ZA50
V33ZTX1
V33ZTX5
V33ZTX70
7mm
14mm
20mm
33TX1
33TX5
33TX70
V33ZA1
V33ZA5
V33ZA70
V420LTX20A
V420LTX40B
14mm
20mm
420TX20
420TX40
V420LA20A
V420LA40B
V68ZTX2
V68ZTX10
7mm
14mm
68TX2
68TX10
V68ZA2
V68ZA10
V480LTX40A
V480LTX80B
14mm
20mm
480TX40
480TX80
V480LA40A
V480LA80B
V82ZTX2
V82ZTX12
7mm
14mm
82TX2
82TX12
V82ZA2
V82ZA12
V510LTX40A
V510LTX80B
14mm
20mm
510TX40
510TX80
V510LA40A
V510LA80B
The TX Series of varistors are 100% screened and conditioned in accordance with MIL-STD-750. These tests are outlined in table 3 below
INSPECTION LOTS
FORMED AFTER
ASSEMBLY
>
LOTS PROPOSED
FOR TX TYPES
>
100% SCREENING
REVIEW OF DATA
TX PREPARA TION
FOR DELIVERY
>
>
QA ACCEPTANCE
SAMPLE PER
APPLICABLE DEVICE
SPECIFICATION
Table 3. TX Equivalents Series 100% Screening
MIL-STD-105
LTPD
LEVEL
AQL
Electrical (Bidirectional)
VN(DC), VC (Per Specifications Table)
II
0.1
-
Dielectric Withstand Voltage
MIL–STD–202, Method 301, 2500V Min. at 1.0µADC
-
-
15
Solderability
MIL–STD–202, Method 208, No Aging, Non-Activated
-
-
15
© 2015 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 11/04/15
Metal-Oxide Varistors (MOVs)
High Reliability Varistors
Table 4. Quality Assurance Acceptance Tests
Screen
High Temperature Life
(Stabilization Bake)
MIL-STD-750
Method
Condition
TX Requirements
1032
24 hours min at max rated storage temperature.
100%
1051
No dwell is required at 25°C. Test condition A1, 5 cycles -55°C to +125°C
(extremes) >10 minutes.
100%
Humidity Life
85°C, 85% RH, 168 Hrs.
100%
Interim Electrical VN(DC) VC
(Note 3)
As specified, but including delta parameter as a minimum.
Thermal Shock
(Temperature Cycling)
Power Burn-In
1038
Final Electrical +VN(DC) VC
(Note 3)
External Visual
Examination
100% Screen
Condition B, 85°C, rated VM(AC), 72 hours min.
100%
As specified - All parameter measurements must be completed within 96
hours after removal from burn-in conditions.
2071
100% Screen
To be performed after complete marking.
100%
3) Custom Types
In addition to our comprehensive high-reliability series, Littelfuse can screen and condition to specific requirements.
Additional mechanical and environmental capabilities are defined in Table 5.
Table 5. Mechanical And Environmental Capabilities (Typical Conditions)
Test Name
Test Method
Description
Terminal Strength
MIL-STD-750-2036
3 Bends, 90° Arc, 16oz. Weight
Drop Shock
MIL-STD-750-2016
1500g’s, 0.5ms, 5 Pulses, X1, V1, Z1
Variable Frequency Vibration
MIL-STD-750-2056
20g’s, 100-2000Hz, X1, V1, Z1
Constant Acceleration
MIL-STD-750-2006
V2, 20,000g’s Min
Salt Atmosphere
MIL-STD-750-1041
35°C, 24Hr, 10-50g/m2 Day
Soldering Heat/Solderability
MIL-STD-750-2031/2026
260°C, 10s, 3 Cycles, Test Marking
Resistance to Solvents
MIL–STD–202-215
Permanence, 3 Solvents
Flammability
MIL–STD–202-111
15s Torching, 10s to Flameout
Cyclical Moisture Resistance
MIL–STD–202-106
10 Days
Steady-State Moisture Resistance
MIL–STD–750-1021.3
85/85 96Hr
Biased Moisture Resistance
MIL–STD–750-1021.3
Not Recommended for High-Voltage Types
Temperature Cycle
MIL–STD–202-107
-55°C to 125°C, 5 Cycles
High-Temperature Life (Nonoperating)
MIL-STD-750-1032
125°C, 24Hr
Burn-In
MIL-STD-750-1038
Rated Temperature and VRMS
Hermetic Seal
MIL-STD-750-1071
Condition D
© 2015 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 11/04/15
Metal-Oxide Varistors (MOVs)
High Reliability Varistors
Radiation Hardness
For space applications, an extremely important property of a
protection device is its response to imposed radiation effects.
Electron Irradiation
A Littelfuse MOV and a Silicon transient suppression diode
were exposed to electron irradiation. The V-I curves, before
and after test, are shown below.
LITTELFUSE MOV
200
100
80
60
PRE TEST
10 8 RADS,
18MeV ELECTRONS
40
It
20
The characteristic voltage current relationship of a P– N
Junction is shown below.
I
10 8
10 6
10 4
10 2
is
CURRENT (A)
FIGURE 1. RADIATION SENSITIVITY OF LITTELFUSE V130LA1
AND SILICON TRANSIENT SUPPRESSION DIODE
apparent that the Littelfuse MOV was virtually unaffected,
even at the extremely high dose of 108 rads, while the
Silicon transient suppression diode showed a dramatic
increase in leakage current.
Neutron Effects
A second MOV-Zener comparison was made in response to
neutron fluence. The selected devices were equal in area.
Figure 2 shows the clamping voltage response of the MOV
and the Zener to neutron irradiation to as high as 1015 N/
cm2. It is apparent that in contrast to the large change in
the Zener, the MOV is unaltered. At highercurrents where
the MOV’s clamping voltage is again unchanged, the Zener
device clamping voltage increases by as much as 36%.
300
1.5K 200 INITIAL
200 VARISTOR V130A2
INITIAL AT 10 15
VOLTS
100
80
60
50
40
1.5K 200
AT 10 12
1.5K 200
AT 10 13
20
1.5K 200
AT 10 14
SATURATION
CURRENT
FORWARD
BIAS
BREAKDOWN
VOLTAGE
V
REDUCTION IN
FAILURE STRESSHOLD
BY RADIAL
SECONDARY
BREAKDOWN
REVERSE
BIAS
FIGURE 3. V-I CHARACTERISTIC OF PN-JUNCTION
At low reverse voltage, the device will conduct very little
current (the saturation current). At higher reverse voltage
VBO (breakdown voltage),the current increases rapidly as
the electrons are either pulled by the electric field (Zener
effect) or knocked out by other electrons (avalanching). A
further increase in voltage causes the device to exhibit a
negative resistance characteristic leading to secondary
breakdown.
This manifests itself through the formation of hotspots,
and irreversible damage occurs. This failure threshold
decreases under neutron irradiation for Zeners, but not for
ZNO Varistors.
30
10
10
The solid and open circles for a given fluence represent the
high and low breakdown currents for the sample of devices
tested. Note that there is a marked decrease in current (or
energy) handling capability with increased neutron fluence.
Failure threshold of Silicon semiconductor junctions is
further reduced when high or rapidly increasing currents
are applied. Junctions develop hot spots, which enlarge
until a short occurs if current is not limited or quickly
removed.
SILICON
TRANSIENT
SUPPRESSION
DIODE
V
Counterclockwise rotation of the V-I characteristics is
observed in Silicon devices at high neutron irradiation
levels; in other words, increasing leakage at low current
levels and increasing clamping voltage at higher current
levels.
1.5K 200
AT 10 15
Gamma Radiation
10
10 8
10 6
10 7
AMPERES
10 5
10 4
10 3
FIGURE 2. V-I CHARACTERISTIC RESPONSE TO NEUTRON
IRRADIATION FOR MOV AND ZENER DIODE
DEVICES
Radiation damage studies were performed on type
V130LA2 varistors. Emission spectra and V-I characteristics
were collected before and after irradiation with 106 rads
Co60 gamma radiation. Both show no change, within
experimental error, after irradiation.
© 2015 Littelfuse, Inc.
Specifications are subject to change without notice.
Revised: 11/04/15
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