High Reliability Varistors High Reliability Series Mechanical and Environmental Testing for Aerospace, Military and High Reliability Applications The high reliability Harris varistor is the latest step in increased product performance, and is available for applications requiring quality and reliability assurance levels consistent with military or other standards. (MIL-STD-19500, MIL-S-750, Method 202). Additionally, Harris varistors are inherently radiation hardened compared to silicon diode suppressors as illustrated in Figure 1. This series of high-reliability varistors involve five categories: * DESC Qualified Parts List (QPL) MIL-R-83530 4 types presently available * Harris high reliability series offers TX equivalents 29 types presently available * Custom types processed to customer-specific requirements - (SCD) or to standard military flow * SP720 - High Reliability Electronic Protection Array Credentials Harris varistors and quality management systems are: * DESC approved * DESC Standard Military Drawings based on MIL-R-83530 63 types presently available: - ZA Series - Drawing #87063 * QPL listed * CECC approved * ISO approved * UL approved - DB Series - Drawing #90065 * CSA approved DESC Qualified Parts List (QPL) MIL-R-83530 TABLE 1. MIL-R-83530/1 RATINGS AND CHARACTERISTICS VOLTAGE RATING (V) NOMINAL VARISTOR ENERGY PART RATING NUMBER VOLTAGE TOLERANCE (RMS) (DC) M83530/ (V) (%) (J) CLAMPING VOLTAGE AT 100A (V) CAPACITANCE AT 1MHz (pF) CLAMPING VOLTAGE AT PEAK CURRENT RATING (V) ITM (A) NEAREST COMMERCIAL EQUIVALENT 1-2000B 200 10 130 175 50 325 3800 570 6000 V130LA20B 1-2200D 220 +10, -5 150 200 55 360 3200 650 6000 V150LA20B 1-4300E 430 +5, -10 275 369 100 680 1800 1200 6000 V275LA40B 1-5100E 510 +5, -10 320 420 120 810 1500 1450 6000 V320LA40B This series of varistors are screened and conditioned in accordance with MIL-R-83530 as outlined in Table 2. Manufacturing system conforms to MIL-I-45208; MIL-Q-9858. 13-3 High Reliability Series MIL-R-83530 Inspections TABLE 2. MIL-R-83530 GROUP A, B, AND C INSPECTIONS AQL (PERCENT DEFECTIVE) MAJOR MINOR NUMBER OF SAMPLE UNITS FAILURES ALLOWED High Temperature Life (Stabilization Bake) 100% - - - - Thermal Shock 100% - - - - Power Burn-In 100% - - - - Clamping Voltage 100% - - - - Nominal Varistor Voltage 100% - - - - Visual and Mechanical Examination - 1.0% AQL 7.6% LQ 25% AQL 13.0% LQ Per Plan - Body Dimensions - Per Plan - Diameter and Length of Leads - Per Plan - Marking - Per Plan - Workmanship - Per Plan - INSPECTION Group A SUBGROUP 1 SUBGROUP 2 SUBGROUP 3 Solderability Group B - - - Per Plan - - - - Per Plan - - - - Per Plan - Terminal Strength (Lead Fatigue) - - - Per Plan - Moisture Resistance - - - Per Plan - Peak Current - - - Per Plan - Energy - - - Per Plan - High Temperature Storage - - - 10 0 Operating Life (Steady State) - - - 10 0 Pulse Life - - - 10 0 Shock - - - 10 0 Vibration - - - 10 0 Constant Acceleration - - - 10 0 Energy - - - 10 0 SUBGROUP 1 Dielectric Withstanding Voltage SUBGROUP 2 Resistance to Solvents SUBGROUP 3 Group C EVERY 3 MONTHS 13-4 High Reliability Series DESC Standard Military Drawing # 87063 Based on MIL-R-83530 TABLE 3. ZA SERIES RATINGS AND SPECIFICATIONS MAXIMUM RATINGS (+85oC) CONTINUOUS RMS 87063 DASH NO. DC NEAREST VM(AC) VM(DC) COMM. (NOTE 1) (V) (V) NO. SIZE SPECIFICATIONS (+25oC) TRANSIENT VARISTOR VOLTAGE AT 1mADC TEST CURRENT MAXIMUM CLAMPING VOLTAGE VC AT TEST CURRENT (8/20s) ENERGY (10/ 1000s) PEAK CURRENT (8/20s) WTM ITM MIN VN(DC) MAX VC IC f = 1MHz (J) (A) (V) (V) (V) (V) (A) (pF) TYPICAL CAPACITANCE 001 V22ZA05 1 14 18 0.2 35 18.7 22 26 51 2 400 002 V22ZA1 2 14 18 0.9 150 18.7 22 26 47 5 1600 003 V22ZA2 3 14 18 2.0 350 18.7 22 26 43 5 4000 004 V22ZA3 4 14 18 4.0 750 18.7 22 26 43 10 9000 005 V24ZA50 5 14 18 6.5 1500 19.2 24 (Note 2) 26 43 20 18000 006 V27ZA05 1 17 22 0.25 35 23 27 31.1 59 2 300 007 V27ZA1 2 17 22 1.0 150 23 27 31.1 57 5 1300 008 V27ZA2 3 17 22 2.5 350 23 27 31.1 53 5 3000 009 V27ZA4 4 17 22 5.0 750 23 27 31.1 53 10 7000 010 V27ZA60 5 17 22 8.0 1500 23 27 (Note 2) 31.1 50 20 15000 011 V33ZA05 1 20 26 0.3 35 29.5 33 38 67 2 250 012 V33ZA1 2 20 26 1.2 150 29.5 33 36.5 68 5 1100 013 V33ZA2 3 20 26 3.0 350 29.5 33 36.5 64 5 2700 014 V33ZA5 4 20 26 6.0 750 29.5 33 36.5 64 10 6000 015 V33ZA70 5 21 27 9.0 1500 29.5 33 (Note 2) 36.5 58 20 13000 016 V36ZA80 5 23 31 10.0 1500 32 36 (Note 2) 40 63 20 12000 017 V39ZA05 1 25 31 0.35 35 35 39 46 79 2 220 018 V39ZA1 2 25 31 1.5 150 35 39 43 79 5 900 019 V39ZA3 3 25 31 3.5 350 35 39 43 76 5 2200 020 V39ZA6 4 25 31 7.2 750 35 39 43 76 10 5000 021 V47ZA05 1 30 38 0.4 35 42 47 55 90 2 200 022 V47ZA1 2 30 38 1.8 150 42 47 52 92 5 800 023 V47ZA3 3 30 38 4.5 350 42 47 52 89 5 2000 024 V47ZA7 4 30 38 8.8 750 42 47 52 89 10 4500 025 V56ZA05 1 35 45 0.5 35 50 56 66 108 2 180 13-5 High Reliability Series TABLE 3. ZA SERIES RATINGS AND SPECIFICATIONS (Continued) MAXIMUM RATINGS (+85oC) CONTINUOUS RMS 87063 DASH NO. DC SPECIFICATIONS (+25oC) TRANSIENT VARISTOR VOLTAGE AT 1mADC TEST CURRENT MAXIMUM CLAMPING VOLTAGE VC AT TEST CURRENT (8/20s) ENERGY (10/ 1000s) PEAK CURRENT (8/20s) WTM ITM MIN VN(DC) MAX VC IC f = 1MHz (J) (A) (V) (V) (V) (V) (A) (pF) NEAREST VM(AC) VM(DC) COMM. (NOTE 1) NO. SIZE (V) (V) TYPICAL CAPACITANCE 026 V56ZA2 2 35 45 2.3 150 50 56 62 107 5 700 027 V56ZA3 3 35 45 5.5 350 50 56 62 103 5 1800 028 V56ZA8 4 35 45 10.0 750 50 56 62 103 10 3900 029 V68ZA05 1 40 56 0.6 35 61 68 80 127 2 150 030 V68ZA2 2 40 56 3.0 150 61 68 75 127 5 600 031 V68ZA3 3 40 56 6.5 350 61 68 75 123 5 1500 032 V68ZA10 4 40 56 13.0 750 61 68 75 123 10 3300 033 V82ZA05 1 50 66 1.2 70 73 82 97 145 2 120 034 V82ZA2 2 50 66 3.5 300 73 82 91 135 10 500 035 V82ZA4 3 50 66 7.3 750 73 82 91 135 25 1100 036 V82ZA12 4 50 66 13.0 1500 73 82 91 145 50 2500 037 V100ZA05 1 60 81 1.5 70 90 100 117 175 2 90 038 V100ZA3 2 60 81 4.3 300 90 100 110 165 10 400 039 V100ZA4 3 60 81 8.9 750 90 100 110 165 25 900 040 V100ZA15 4 60 81 16.0 1500 90 100 110 175 50 2000 041 V120ZA05 1 75 102 1.8 100 108 120 138 205 2 70 042 V120ZA1 2 75 102 5.3 400 108 120 132 205 10 300 043 V120ZA4 3 75 102 11.0 1000 108 120 132 200 25 750 044 V120ZA6 4 75 102 19.0 2000 108 120 132 210 50 1700 045 V150ZA05 1 92 127 2.3 100 135 150 173 240 2 60 046 V150ZA1 2 95 127 6.5 400 135 150 165 250 10 250 047 V150ZA4 3 95 127 13.0 1000 135 150 165 250 25 600 048 V150ZA8 4 95 127 23.0 2000 135 150 165 255 50 1400 049 V180ZA05 1 110 153 2.7 150 162 180 207 290 2 50 050 V180ZA1 2 115 153 7.7 500 162 180 198 295 10 200 051 V180ZA5 3 115 153 16.0 1500 162 180 198 300 25 500 052 V180ZA10 4 115 153 27.0 3000 162 180 198 300 50 1100 NOTES: 1. Size 1-5mm, 2-7mm, 3-10mm, 4-14mm, 5-20mm 2. 10mA DC test current. 13-6 High Reliability Series DESC Standard Military Drawing # 90065 Based on MIL-R-83530 TABLE 4. DB SERIES RATINGS AND SPECIFICATIONS 90065 DASH NO. VOLTAGE RATING MAX. (RMS) NOMINAL VARISTOR VOLTAGE (V) ENERGY MAX (J) PEAK CURRENT (A) 012 130 170 22500 200 013 150 200 22500 014 250 270 015 275 016 MAX CLAMPING VOLTAGE AT TEST CURRENT (V) (I) TYPICAL CAPACITANCE (pF) +28, -16 345 200 10000 240 28 405 200 8000 22500 390 +39, -36 650 200 5000 300 22500 430 43 730 200 4500 320 350 22500 510 +29, -48 830 200 3800 017 420 460 28800 680 +68, -70 1130 200 3000 018 480 510 28800 750 +74, -80 1240 200 2700 019 510 550 28800 820 +91, -85 1350 200 2500 020 575 600 28800 910 +95, -105 1480 200 2200 021 660 690 28800 1050 110 1720 200 2000 022 750 810 28800 1200 120 2000 200 1800 Harris High Reliability Series TX Equivalents TABLE 5. AVAILABLE TX MODEL TYPES NEAREST COMMERCIAL EQUIVALENT MODEL SIZE DEVICE MARK V8ZTX1 7mm 8TX1 V8ZA1 V8ZTX2 10mm 8TX2 V12ZTX1 7mm V12ZTX2 NEAREST COMMERCIAL EQUIVALENT MODEL SIZE DEVICE MARK V130LTX2 7mm 130TX V8ZA2 V130LTX10A 14mm 130TX10 V130LA10A 12TX1 V12ZA1 V130LTX20B 20mm 130TX20 V130LA20A 10mm 12TX2 V12ZA2 V150LTX2 7mm 150TX V22ZTX1 7mm 22TX1 V22ZA1 V150LTX10A 14mm 150TX10 V150LA10A V22ZTX3 14mm 22TX3 V22ZA3 V150LTX20B 20mm 150TX20 V150LA20B V24ZTX50 20mm 24TX50 V24ZA50 V250LTX4 7mm 250TX V33ZTX1 7mm 33TX1 V33ZA1 V250LTX20A 14mm 250TX20 V250LA20A V33ZTX5 14mm 33TX5 V33ZA5 V250LTX40B 20mm 250TX40 V250LA40B V33ZTX70 20mm 33TX70 V33ZA70 V420LTX20A 14mm 420TX20 V420LA20A V68ZTX2 7mm 68TX2 V68ZA2 V420LTX40B 20mm 420TX40 V420LA40B V68ZTX10 14mm 68TX10 V68ZA10 V480LTX40A 14mm 480TX40 V480LA40A V82ZTX2 7mm 82TX2 V82ZA2 V480LTX80B 20mm 480TX80 V480LA80B V82ZTX12 14mm 82TX12 V82ZA12 V510LTX40A 14mm 510TX40 V510LA40A V510LTX80B 20mm 510TX80 V510LA80B TX MODEL TX MODEL 13-7 V130LA2 V150LA2 V250LA4 High Reliability Series The TX series of varistors are 100% screened and conditioned in accordance with MIL-STD-750. Tests are as outlined in Table 6. INSPECTION LOTS FORMED AFTER ASSEMBLY LOTS PROPOSED FOR TX TYPES QA ACCEPTANCE REVIEW OF DATA 100% SCREENING SAMPLE PER TX PREPARATION APPLICABLE DEVICE FOR DELIVERY SPECIFICATION TABLE 6. TX EQUIVALENTS SERIES 100% SCREENING SCREEN MIL-STD-750 METHOD TX REQUIREMENTS CONDITION High Temperature Life (stabilization bake) 1032 24 hours min. at max. rated storage temperature. 100% Thermal Shock (temperature cycling) 1051 No dwell is required at 25oC. Test condition A1, 5 cycles -55oC to +125 oC (extremes). >10 minutes 100% Humidity Life 85oC, 85% R.H., 168 hours. 100% Interim Electrical VN(DC) VC (Note 1) As specified, but including delta parameter as a minimum. Power Burn-In 1038 Final Electrical +VN(DC) VC (Note 1) External Visual Examination Condition B, 85oC, 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% Screen 100% NOTE: 1. Delta Parameter - VN(DC) Maximum allowable shift 10% Max. Applicable lot PDA - 10% Max. Peak current and energy ratings are derated by 10% and 30%, respectively, from standard parts. TABLE 7. QUALITY ASSURANCE ACCEPTANCE TEST MIL-STD-105 LEVEL AQL LTPD Electrical (Bidirectional) VN(DC), VC (Per specifications table) II 0.1 - Dielectric Withstand Voltage MIL-STD-202, Method 301, 2500V min. at 1.0ADC - - 15 Solderability MIL-STD-202, Method 208, no aging, non-activated - - 15 13-8 High Reliability Series Custom Types In addition to our comprehensive high-reliability series as referenced above, Harris can screen and condition to customer-specific requirements. Additional mechanical and environmental capabilities are defined in Table 8. TABLE 8. MECHANICAL AND ENVIRONMENTAL CAPABILITIES (TYPICAL CONDITIONS) TEST NAME TEST METHOD DESCRIPTION Terminal Strength MIL-STD-750-2036 3 Bends, 90o 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 35oC, 24 hrs, 10-50g/m2 Day Soldering Heat/Solderability MIL-STD-750-2031/2026 260oC, 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 Flammability UL1414 Cyclical Moisture Resistance 3 x 15s Torching MIL-STD-202-106 10 Days Steady-State Moisture Resistance 85/85 96 Hrs. Biased Moisture Resistance Not Recommended for High-Voltage Types Temperature Cycle MIL-STD-202-107 -55oC to +125oC, 5 Cycles High-Temperature Life (Nonoperating) MIL-STD-750-1032 125oC, 24 Hrs. Burn-In MIL-STD-750-1038 Rated Temperature and VRMS Hermetic Seal MIL-STD-750-1071 Condition D Radiation Hardness For space applications, an extremely important property of a protection device is its response to imposed radiation effects. HARRIS MOV 200 SILICON TRANSIENT SUPPRESSION DIODE V Electron Irradiation 100 A Harris MOV and a silicon transient suppression diode were exposed to electron irradiation. The V-I Curves, before and after test, are shown in Figure 1. It is apparent that the Harris 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. 80 60 PRE TEST 108 RADS, 18MeV ELECTRONS 40 20 108 106 104 CURRENT (A) 102 FIGURE 1. RADIATION SENSITIVITY OF HARRIS V130LA1 AND SILICON TRANSIENT SUPPRESSION DIODE 13-9 High Reliability Series Neutron Effects A second MOV-Zener comparison was made in response to neutron fluence. The selected devices were equal in area. The characteristic voltage current relationship of a PN-Junction is shown in Figure 3. I 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 higher currents where the MOV's clamping voltage is again unchanged, the zener device clamping voltage increases by as much as 36%. SATURATION CURRENT BREAKDOWN VOLTAGE V 300 REDUCTION IN FAILURE STRESSHOLD BY RADIAL 1.5K 200 INITIAL VOLTS 200 VARISTOR V130A2 INITIAL AT 1015 100 80 60 50 40 SECONDARY BREAKDOWN REVERSE BIAS 1.5K 200 AT 1012 FIGURE 3. V-I CHARACTERISTIC OF PN-JUNCTION 30 1.5K 200 AT 1013 20 10 10 FORWARD BIAS 10 108 1.5K 200 AT 1014 1.5K 200 AT 1015 106 107 AMPERES 105 104 103 FIGURE 2. V-I CHARACTERISTIC RESPONSE TO NEUTRON IRRADIATION FOR MOV AND ZENER DIODE DEVICES 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. 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. This manifests itself through the formation of hotspots, and irreversible damage occurs. This failure threshold decreases under neutron irradiation for zeners, but not for Zinc Oxide Varistors. 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. Gamma Radiation 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. 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. 13-10