Transient Protection - MLVs

AVXRon Demcko 3900 Electronics DriveRaleigh, N.C. 27604rdemcko@avxus.com919-878-6224 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