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Transient Protection - MLVs. AVX Ron Demcko 3900 Electronics Drive Raleigh, N.C. 27604 [email protected] 919-878-6224 phone 919-878-6218 fax. Protection Schemes MultiLayer Varistors (MLVs) TVS Diodes. Typical Protection Schemes Circuit Implementation. MultiLayer Varistors (MLVs). - PowerPoint PPT Presentation
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Transient Protection - MLVs
AVXRon Demcko 3900 Electronics DriveRaleigh, N.C. [email protected] phone919-878-6218 fax
Protection Schemes
• MultiLayer Varistors (MLVs)
• TVS Diodes
Typical Protection Schemes Circuit Implementation
MultiLayer Varistors (MLVs) TVS Diodes
TVSTVS & EMINeedEMCCap
SEE AVX SAE Tech paper for more details
5 component solution
AVX = SINGLE PART SOLUTION
0805 CASE SIZE 0603 CASE SIZE REFERENCE ______________ ______________ _________ VC080518A400 VC060318A400 MMBZ Type 18V 18V (18V) DC OPERATING VOLTAGE 22.9 - 28.0 V 22.9 - 28.0 V 25.65-28.35V BREAKDOWN VOLTAGE 40V @1A 40V @1A 38V @1A CLAMPING VOLTAGE 0.1J 0.1J ENERGY RATING 40W 40W 40W PEAK POWER DISSIPATION @1ms 225mw 225mw 225mw Pd FR-4 300mw 300mw 300mw TOTAL POWER DISSIPATION ON ALUMINA -55C TO 150C -55C TO 150C -55C TO 150C JUNCTION AND STORAGE TEMPERATURE RANGE 198 TO 300 PF 112 TO 300 PF <60 PF CAPACITANCE OVER TEMPERATURE
MLV vs Diode Comparison
Note: Several MLV CAN Parts exist: <40, 60, 120, 220 & 470 pf
AVX Corporation 3900 Electronics Dr. Raleigh, NC 27604
AVX VC080518A TransGuardTypical S21
-50
-45
-40
-35
-30
-25
-20
-15
-10
-5
0
0.01 0.1 1 10
FREQUENCY (GHz)
dB
39 v Zener SOD 123
Dashed line indicated S21 available with MLVs
0805 Device 0603 Device ARRAY TYPE 60pF ± 20% VC08LC18A500 VC06LC18X500 MG052L18X500
min max min max min maxVaristor Voltage 25 35 25 35 25 35
(Vb)
Clamping Voltage 25 75 25 75 25 75 HIGH SPEED CANat 7.5A
Clamping Voltage 25 50 25 50 25 50at 1A
Leakage Current 25 25 25at 10.5V
Leakage Current 100 100 100at 16V
120pF ± 20% VC080526A580 VC060330A650 No Part Availablemin max min max min max
Varistor Voltage 31 38 36.5 45.5 N/A N/A(Vb)
Clamping Voltage 25 75 25 75 N/A N/A
at 7.5A LOW SPEED CANClamping Voltage 25 60 25 67 N/A N/A
at 1ALeakage Current 25 25 N/A N/A
at 10.5VLeakage Current 100 100 N/A N/A
at 16V
220pF ± 20% VC080518A400 VC060318A400 MG052S18A400min max min max min max
Varistor Voltage 22.9 28 22.9 28 22.9 28(Vb)
Clamping Voltage 25 75 25 75 25 75
at 7.5A LOW SPEED CANClamping Voltage 25 42 25 42 25 42
at 1ALeakage Current 25 25 25
at 10.5VLeakage Current 100 100 100
at 16V
100
25
5024
7524
35**24
maxmin
MG042L18V500
35** under evaluation for 30v
MMBZ Type Diode
# Cap (pF)IL @30V (nA)
Breakdown @ 1mA
Clamping Voltage 8/20 @ 1 Amp
Clamping Voltage 8/20 @ 20 Amp
Clamping Voltage10/700 @ 1 Amp
500 strikes1 42 <100 37.63 40 short short2 42 <100 38.19 41.2 short short3 42 <100 38.14 41 short short4 42 <100 38.32 41.1 short short5 42 <100 38.5 41.5 short short
All parts failed 20 Amp maximum 8/20 pulse rating with 500 strikes. Strikes were Uni-directional
All parts failed1 Amp maximum 10/700 pulse rating with 500 strikes. Strikes were Uni -directional
All components failed short
39V Zener diodeUni-directional SOT 323
Diode Repetitive Surge Test Results
MLVs – Multi Layer Varistors
MLVs
• Available in discrete & Array Forms• EMI Filter in Off State• Back to Back Zener in on state• High In Rush Current Capability• Sub ns Turn On Time• High ESD repetitive Strike Capability• No Temperature De-rating to 125 c• Small Size
MLVs – Multi Layer Varistors
FeedThru MLVs
• Available in discrete & Array Forms• EMI Filter in Off State – HIGH Q Filter• Back to Back Zener in on state• High In Rush Current Capability• Sub ns Turn On Time• High ESD repetitive Strike Capability• No Temperature De-rating to 125 c• Small Size
-10%
-5%
0%
5%
10%
15%
-100 -50 0 50 100 150
Temperature [°C]
Cha
nge
in C
apac
itanc
e [%
]
MLV Capacitance Temperature Stability
• Working Voltage = voltage at which the part can operate indefinitely current is </= 50 ua
• Breakdown Voltage = voltage at which the part draws 1 ma of current
• Clamping Voltage = voltage the part limits to when subjected to an 8x20us waveform (current varies with energy rating)
• Peak Current = maximum 8x20us repetitive strike (500 pulses) current rating
• Transient Energy = maximum 10x1000us energy in Joules
MLV Terminology
Initial Initial Initial Clamping Voltage @20 Amps Post Post Post
# CAP(pf) VB (V) IL (nA) CAP(pf) VB (V) IL (nA)
1 285 23.43 733 44.6 274 25.37 4582 254 26.42 195 47.2 245 27.86 3433 266 23.3 583 48.4 175 26.64 3744 276 23.71 364 44.0 262 25.15 5005 283 23.30 511 44.2 268 24.96 3756 269 24.13 312 44.7 256 25.37 4277 264 24.13 278 45.2 253 25.67 2778 272 23.17 859 43.8 259 25.57 2869 273 23.64 500 44.6 260 25.15 584
10 263 23.3 583 44.0 249 24.96 109411 289 23.17 799 43.9 272 25.37 22412 253 24.13 202 45.6 240 26.20 26813 282 23.69 647 44.3 266 25.37 43814 252 27.06 122 46.7 238 27.99 13115 259 26.64 143 50.1 246 28.82 16616 275 23.3 735 43.3 258 24.96 50317 279 23.86 437 43.9 259 25.15 108018 288 23.59 559 43.3 267 24.96 36919 275 24.05 354 44.9 253 26.20 17320 256 23.71 583 43.5 231 25.37 334
VC080518A400 500 STRIKE 8/20 TEST
MLV Repetitive Strike 8/20 us Surge Response
Initial Initial Initial Clamping Voltage @5 Amps Post Post Post
# CAP(pf) VB (V) IL (nA) CAP(pf) VB (V) IL (nA)
1 272 23.3 1.01 39.8 262 24.52 16.68
2 279 24.13 0.41 41.6 266 27.06 2.82
3 266 26.4 0.16 42.6 262 26.42 16.56
4 275 23.91 0.56 40.9 263 25.79 6.66
5 270 24.13 0.30 41.7 257 26.64 2.75
6 272 23.17 0.77 40.1 261 26.35 2.16
7 271 23.30 0.77 39.8 260 25.71 5.83
8 279 24.13 0.44 41.4 263 27.89 220.00
9 289 23.17 0.70 40.2 270 25.57 9.57
10 265 25.15 0.35 41.1 265 25.57 27.52
11 280 23.71 0.76 40.3 262 26.57 2.45
12 260 23.91 0.37 42.2 237 28.72 0.13
13 284 24.54 0.52 40.3 270 24.74 37.51
14 262 23.27 0.76 40.8 241 26.64 1.95
15 300 23.3 0.76 40.2 275 26.64 0.28
16 266 23.71 0.41 40.9 246 26.64 2.45
17 276 24.96 0.20 42.6 253 28.08 0.63
18 260 26.2 0.22 42.4 248 27.81 5.00
19 270 24.32 0.87 41.4 244 28.18 1.10
20 285 23.22 0.87 40.2 258 26.20 2.31
VC080518A400 500 STRIKE 10/700 TEST
MLV Repetitive Strike 10/700 us Surge Response
# CAP VB IL VC READINGS CAP VB IL VC1 255.628 27.06 187.5NA 34.9 .622MA 243.766 27.35 172.9NA 35.42 251.672 23.49 630.3NA 31.5 7.165MA 242.497 24.13 10.26UA 33.13 267.922 23.49 1072NA 31.6 7.789MA 257.897 24.13 22.56UA 33.04 267.364 23.30 773.4NA 31.6 6.122MA 256.138 24.32 4.010UA 33.15 282.030 24.00 395.8NA 32.6 5.221MA 270.810 24.74 333.6NA 33.66 272.991 24.00 510.4NA 32.8 4.512MA 262.755 24.74 362.4NA 33.97 277.235 23.30 734.3NA 31.6 5.672MA 264.564 24.96 2.203UA 33.28 266.881 23.30 1000NA 31.3 8.351MA 254.868 23.71 13.24UA 32.79 269.380 23.30 677.9NA 31.5 6.630MA 256.242 23.96 7.917UA 33.1
10 239.652 25.25 169.5NA 33.8 2.826MA 227.276 25.79 158.5NA 34.511 286.280 23.59 677.2NA 32.3 6.910MA 273.560 24.32 500.1NA 33.412 266.047 23.91 458.4NA 33.0 3.685MA 253.408 24.74 5.104UA 34.013 256.106 27.89 100.1NA 37.1 .253MA 244.261 28.03 100.1NA 37.614 262.085 26.20 216.8NA 34.1 1.380MA 248.535 26.57 583.4NA 34.715 269.109 23.17 518.2NA 32.0 6.810MA 254.597 23.91 4.589UA 33.416 257.073 23.71 609.3NA 31.3 7.580MA 240.897 24.42 8.854UA 32.817 269.490 26.20 132.8NA 35.2 1.202MA 255.974 26.64 122.1NA 35.818 275.234 25.79 265.0NA 33.9 1.590MA 259.941 26.35 645.9NA 34.419 280.478 24.96 520.9NA 32.6 3.265MA 262.668 25.52 2.752UA 33.520 272.994 23.69 500.1NA 31.9 7.622MA 251.636 25.79 143.8NA 32.4
VC080518A400 Jump Start Test
AFTER27.5 V LEAKAGE
TEST FOR 5 MINUTES
BEFORE
Temperature Advantages of MLV
0%
20%
40%
60%
80%
100%
120%
0 50 100 150 200
Temperature [°C]
% o
f R
ated
Po
wer
MultiLayer Varistor
Diode
MLVs maintain Energy ratingwithout de rating up to 125 C
Size Advantages of MLVs
0.067” 0.112”
0.020” 0.142”
Total Area = Total Area = 0.00134 in2 0.01590 in2
0402 TransGuard SOT 23 Diode & EMC Cap
MLVs are 91.5 % SMALLER
Summary
• AVX MLVs can replace MMBZ diodes for ESD suppression• AVX MLV can be placed on the EMC capacitor pad – no board spin• MLV exhibit physical & electrical advantages to control EMC
• large surge capability• repetitive strike – no wear out• EMI filtering in the off state• Low & Hi Q Response• Temperature stability• Small size/ low weight