Varistor Products
Surface Mount Multilayer Varistors (MLVs) > ML Series
RoHS
ML Varistor Series
Description
The ML Series family of transient voltage surge
suppression devices is based on the Littelfuse Multilayer
fabrication technology. These components are designed
to suppress a variety of transient events, including those
specified in IEC 61000-4-2 or other standards used for
Electromagnetic Compliance (EMC). The ML Series is
typically applied to protect integrated circuits and other
components at the circuit board level.
The wide operating voltage and energy range make the ML
Series suitable for numerous applications on power supply,
control and signal lines.
Size Table
Metric
1005
1608
2012
0805
1206
1210
EIA
0402
The ML Series is manufactured from semiconducting
ceramics, and is supplied in a leadless, surface mount
package. The ML Series is compatible with modern reflow
and wave soldering procedures.
It can operate over a wider temperature range than Zener
diodes, and has a much smaller footprint than plastic-
housed components.
Littelfuse Inc. manufactures other multilayer series
products. See the MLE Series data sheet for ESD
applications, MHS Series data sheet for high-speed ESD
applications, the MLN Series for multiline protection and
the AUML Series for automotive applications.
electromagnetic
compliance of
end products
mount TVS Zeners in
many applications
Applications
switching or other
transient events such as
EFT and surge voltage at
the circuit board level
61000-4-2, MIL-STD-
and other industry
specifications (see also
the MLE or MLN Series)
transient voltage
protection for ICS
and transistors
Features
current (8 x 20μs)
(10 x 1000μs)
clamping
packaging assures
better than UL94V-0
flammability rating
types available
RoHS compliant
0805, 1206 and
1210 chip sizes
construction technology
operating temp. range
V
M(DC)
= 5.5V to 120V
Absolute Maximum Ratings
For ratings of individual members of a series, see device ratings and specifications table
.
Continuous
Steady State Applied Voltage:
DC Voltage Range (V
M(DC)
)
AC Voltage Range (V
M(AC)RMS
)
Transient:
Non-Repetitive Surge Current, 8/20μs Waveform, (I
TM
)
Non-Repetitive Surge Energy, 10/1000μs Waveform, (W
TM
)
)
A
Storage Temperature Range (T
STG
)
Temperature Coefficient (αV) of Clamping Voltage (V
C
) at
Specified Test Current
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ML.html for current information.
37
Revision: July 16, 2009
ML Series
Units
V
V
4 to 500
0.02 to 2.5
A
J
ºC
ºC
%/º C
ML Varistor Series
<0.01
ML Series
Surface Mount Multilayer Varistors (MLVs) > ML Series
Varistor Products
Device Ratings and Specifications
Maximum Ratings (125º
C)
Specifications (25ºC)
Maximum
Maximum Non- Maximum Non- Maximum Clamping Nominal Voltage
Typical
Continuous
repetitive Surge repetitive Surge Voltage at 1A (or as at 1mA DC Test Capacitance
Working Voltage Current (8/20μs) Energy (10/1000μs)
Noted) (8/20μs)
Current
at f = 1MHz
V
N(DC)
V
N(DC)
V
M(DC)
V
M(AC)
I
TM
W
TM
V
C
C
Min
Max
(V)
(V)
(A)
(J)
(V)
(V)
(V)
(pF)
2.5
0.100
2.5
120
2.5
40
0.100
2.5
100
6000
5.5
4.0
20
0.050
21.0
10.8
220
5.5
4.0
20
0.050
15.9
21.5
5.5
4.0
0.100
5.5
4.0
0.100
450
5.5
4.0
120
1840
5.5
4.0
40
0.100
990
5.5
4.0
150
0.400
9.0
6.5
20
0.050
11.0
16.0
120
9.0
6.5
4
0.020
11.0
16.0
9.0
6.5
0.100
25.5
11.0
16.0
490
9.0
6.5
0.100
25.5
11.0
16.0
9.0
6.5
40
0.100
25.5
11.0
16.0
520
12.0
9.0
40
0.100
29.0
14.0
18.5
410
14.0
10.0
20
0.050
15.9
21.5
14.0
10.0
0.100
15.9
21.5
180
14.0
10.0
120
15.9
560
14.0
10.0
40
0.100
15.9
14.0
10.0
150
0.400
15.9
1400
18.0
14.0
20
0.050
50.0
22.0
28.0
40
18.0
14.0
0.100
50.0
22.0
28.0
120
18.0
14.0
120
44.0
22.0
28.0
520
18.0
14.0
40
0.100
44.0
22.0
28.0
290
18.0
14.0
150
0.400
44.0
22.0
28.0
18.0
14.0
500
2.500
44.0 at 2.5
22.0
28.0
1440
26.0
20.0
0.100
60.0
110
26.0
20.0
100
60.0
29.5
220
140
26.0
20.0
40
0.100
60.0
29.5
26.0
20.0
150
0.600
60.0
29.5
600
1.200
60.0 at 2.5
29.5
1040
26.0
20.0
25.0
0.100
46.0
90
25.0
0.100
46.0
90
25.0
280
1.200
68.0 at 2.5
1820
25.0
220
0.900
68.0 at 2.5
0.800
49.0
500
26.0
180
42.0
180
0.800
92.0
46.0
60.0
425
48.0
40.0
250
1.200
105.0 at 2.5
54.5
66.5
520
48.0
40.0
220
0.900
105.0 at 2.5
54.5
66.5
500
56.0
40.0
180
1.000
120.0
61.0
180
60.0
50.0
250
1.500
440
68.0
50.0
180
1.000
140.0
90.0
100
85.0
250
2.500
180.0 at 2.5
95.0
115.0
260
120.0
125
2.000
260.0 at 2.5
165.0
80
Part Number
5
V5.5MLA0402N
V5.5MLA0402LN
5
4
V5.5MLA0805N
V5.5MLA0805LN
V5.5MLA1206N
V9MLA0402N
V9MLA0402LN
5
4
V9MLA0805LN
V12MLA0805LN
V14MLA0402N
V14MLA0805N
V14MLA0805LN
V14MLA1206N
V18MLA0402N
V18MLA0805N
V18MLA0805LN
V18MLA1206N
V18MLA1210N
V26MLA0805N
V26MLA0805LN
V26MLA1206N
V26MLA1210N
V42MLA1206N
V48MLA1210N
V48MLA1210LN
V56MLA1206N
V60MLA1210N
V68MLA1206N
V85MLA1210N
V120MLA1210N
1 'L' suffix is a low capacitance and energy version; Contact your Littelfuse sales representative for custom capacitance requirements
2 Typical leakage at 25ºC<25μA, maximum leakage 100μA at V
M(DC)
; for 0402 size, typical leakage <5μA, maximum leakage <20μA at V
M(DC)
ML Varistor Series
38
Revision: July 16, 2009
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ML.html for current information.
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > ML Series
Peak Current and Energy Derating Curve
When transients occur in rapid succession, the average
power dissipation 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
temperature, the peak surge current and energy ratings
must be derated as shown below.
PERCENT OF RATED VALUE
Peak Pulse Current Test Waveform for Clamping Voltage
PERCENT OF PEAK VALUE
100
50
0
T
O
1
T
1
T
2
TIME
100
80
60
40
20
0
-55
50
60
70
80
90
100
110
120
130 140 150
Figure 2
0
1
T
1
= Rise Time = 1.25 x T
T
2
= Decay Time
Example
- For an 8/20
μ
8μs = T
1
= Rise Time
20μs = T
2
= Decay Time
Figure 1
AMBIENT TEMPERATURE (
o
C)
Limit V-I Characteristic for V5.5MLA0402 to V18MLA0402
Limit V-I Characteristic for V9MLA0402L
100
100
Varistor Voltage (V)
Varistor Voltage (V)
10
V18MLA0402
V14MLA0402
V9MLA0402
V5.5MLA0402
10
V9MLA0402L
V5.5MLA0402L
1
1μA
10μA
100μA
1mA
Current (A)
10mA
1A
10A
100A
1
1μA
10μA
100μA
1mA
10mA
1A
10A
100A
Figure 3
Figure 4
Current (A)
Limit V-I Characteristic for V3.5MLA0603 to V30MLA0603
1000
Limit V-I Characteristic for V3.5MLA0805L to V30MLA0805L
1000
V30MLA0805L
V26MLA0805L
V18MLA0805L
V30MLA0603
V26MLA0603
V18MLA0603
Varistor Voltage (V)
V14MLA0603
Varistor Voltage (V)
100
100
V14MLA0805L
10
V12MLA0805L
V9MLA0805L
V5.5MLA0805L
V3.5MLA0805L
10
V9MLA0603, V9MLA0603L
V5.5MLA0603, V5.5MLA0603L
V3.5MLA0603
1
10
μA
1
10μA
100
μA
1mA
10mA
Current (A)
100mA
1A
10A
100A
100μA
1mA
10mA
Current (A)
100mA
1A
10A
100A
Figure 5
Figure 6
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ML.html for current information.
39
Revision: July 16, 2009
ML Varistor Series
ML Series
Surface Mount Multilayer Varistors (MLVs) > ML Series
Varistor Products
Limit V-I Characteristic for V3.5MLA0805 to V26MLA0805
Limit V-I Characteristic for V3.5MLA1206 to V68MLA1206
1000
1000
Varistor Voltage (V)
100
100
Varistor Voltage (V)
10
V26MLA0805
V18MLA0805
V14MLA0805
V5.5MLA0805
V3.5MLA0805
10
V68MLA1206
V56MLA1206
V42MLA1206
V33MLA1206
V26MLA1206
V18MLA1206
V14MLA1206
V5.5MLA1206
V3.5MLA1206
1
10μA
100μA
1mA
10mA
100mA
Current (A)
1A
10A
100A
1000A
1
10
μA
Figure 7
100
μA
1mA
10mA
Figure 8
100mA
Current (A)
1A
10A
100A
1000A
Limit V-I Characteristic for V18MLA1210 to V120MLA1210
1000
MAXIMUM CLAMPING VOLTAGE
MAXIMUM LEAKAGE
100
Varistor Voltage (V)
V120MLA1210
10
V85MLA1210
V60MLA1210
V48MLA1210, V48MLA1210L
V30MLA1210, V30MLA1210L
V26MLA1210
1
10μA
V18MLA1210
100μA
1mA
10mA
100mA
1A
10A
100A
1000A
Figure 9
CURRENT (A)
ML Varistor Series
40
Revision: July 16, 2009
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ML.html for current information.
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > ML Series
Device Characteristics
At low current levels, the V-I curve of the multilayer
transient voltage suppressor approaches a linear (ohmic)
relationship and shows a temperature dependent effect.
At or below the maximum working voltage, the suppressor
is in a high resistance modex (approaching 10
6
Ω at its
maximum rated working voltage). Leakage currents at
maximum rated voltage are below 100μA, typically 25μA;
for 0402 size below 20μA, typically 5μA.
Typical Temperature Dependance of the Haracteristic
Curve in the Leakage Region
100%
SUPPRESSOR VOLTAGE IN PERCENT OF
Clamping Voltage Over Temperature (V
C
at 10A)
100
CLAMPING VOLTAGE (V)
V26MLA1206
V5.5MLA1206
10
-60
-40
-20
0
T
V
NOM
VALUE A 25
o
C (%)
Figure 11
Energy Absorption/Peak Current Capability
Energy dissipated within the ML Series is calculated
by multiplying the clamping voltage, transient current
and transient duration. An important advantage of the
multilayer is its interdigitated electrode construction within
the mass of dielectric material. This results in excellent
current distribution and the peak temperature per energy
absorbed is very low. The matrix of semiconducting grains
combine to absorb and distribute transient energy (heat)
(see Speed of Response). This dramatically reduces peak
temperature; thermal stresses and enhances device
reliability.
As a measure of the device capability in energy and peak
current handling, the V26MLA1206A part was tested with
multiple pulses at its peak current rating (150A, 8/20μs). At
the end of the test,10,000 pulses later, the device voltage
characteristics are still well within specification.
25
10%
1E
-9
1E
-8
o
50
o
75
o
1E
-7
100
o
125
o
C
1E
-6
1E
-5
1E
-4
1E
-3
1E
-2
Figure 10
SUPPRESSOR CURRENT (A
DC
)
Speed of Response
The Multilayer Suppressor is a leadless device. Its
response time is not limited by the parasitic lead
inductances found in other surface mount packages.
The response time of the Z
N
than 1ns and the ML can clamp very fast dV/dT events
such as ESD. Additionally, in "real world" applications,
the associated circuit wiring is often the greatest
factor effecting speed of response. Therefore, transient
suppressor placement within a circuit can be considered
important in certain instances.
Multilayer Internal Construction
FIRED CERAMIC
DIELECTRIC
100
PEAK CURRENT = 150A
8/20 s DURATION, 30s BETWEEN PULSES
METAL
ELECTRODES
METAL END
TERMINATION
VOLTAGE
V26MLA1206
DEPLETION
REGION
10
0
2000
4000
6000
NUMBER OF PULSES
8000
10000
12000
Figure 13
DEPLETION
REGION
Figure 12
GRAINS
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/ML.html for current information.
41
Revision: July 16, 2009
ML Varistor Series
ML Series
20
40
60
80
TEMPERATURE (
o
C)
100
120
140
