Varistor Products
Surface Mount Multilayer Varistors (MLVs) > MLE Series
RoHS
MLE Varistor Series
Description
The fabrication method and materials of these devices
result in capacitance characteristics suitable for high
frequency attenuation/low-pass filter circuit functions,
thereby providing suppression and filtering in a single
device.
Size Table
Metric
EIA
0402
1608
2012
1206
The MLE Series is manufactured from semiconducting
ceramics and is supplied in a leadless, surface mount
package. The MLE Series is compatible with modern reflow
and wave soldering procedures.
Littelfuse Inc. manufactures other Multilayer Series
products. See the ML Series data sheet for higher energy/
peak current transient applications. See the AUML Series
for automotive applications and the MLN Quad Array. For
high–speed applications see the MHS Series.
Applications
t 1SPUFDUJPOPG
components and
circuits sensitive
to ESD Transients
occurring on power
supplies, control
and signal lines
t 4VQQSFTTJPOPG
ESD events such
as specified in
IEC-61000-4-2 or
.*-45%$
.FUIPEGPS
Features
electromagnetic
compliance (EMC)
t "&$2DPNQMJBOU
t 6TFEJONPCJMF
communications,
DPNQVUFS&%1
products, medical
products, hand held/
portable devices,
industrial equipment,
including diagnostic
port protection and
*0JOUFSGBDFT
t 3P)4$PNQMJBOU
t $UP$
operating temp. range
t 3BUFEGPS&4%
(IEC-61000-4-2)
t -FBEMFTT
BOETJ[FT
t $IBSBDUFSJ[FEGPS
impedance and
capacitance
t 0QFSBUJOHWPMUBHFT
up to 18VM(DC)
t .VMUJMBZFSDFSBNJD
construction technology
Absolute Maximum Ratings
t'PSSBUJOHTPGJOEJWJEVBMNFNCFSTPGBTFSJFTTFFEFWJDFSBUJOHTBOETQFDJmDBUJPOTUBCMF
Continuous
MLE Series
Units
Steady State Applied Voltage:
%$7PMUBHF3BOHF7M(DC))
≤18
V
0QFSBUJOH"NCJFOU5FNQFSBUVSF3BOHF5A)
UP
$
4UPSBHF5FNQFSBUVSF3BOHF5STG)
UP
C
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/MLE.html for current information.
31
Revision: July 16, 2009
MLE Varistor Series
MLE Series
The MLE Series family of transient voltage suppression
devices are based on the Littelfuse multilayer fabrication
technology. These components are designed to suppress
ESD events, including those specified in IEC 61000-4-2
or other standards used for Electromagnetic Compliance
testing. The MLE Series is typically applied to protect
integrated circuits and other components at the circuit
board level operating at 18VDC, or less.
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > MLE Series
Device Ratings and Specifications
Max Continuous
Working Voltage
-55ºC to 125ºC
Part Number
Nominal
Voltage
V/0. at
1mA DC
MIN (V) MAX (V)
22
28
22
28
22
28
(Note 1)
VM(DC)
V18MLE0402N
7.-&/
7.-&-/
(V)
18
18
18
7.-&/
7.-&-/
V18MLE1206N
18
18
18
Performance Specifications (25ºC)
Maximum Clamping
Maximum ESD Clamp
Voltage at Specified
Voltage (Note 2)
Current (8/20μs)
22
22
22
28
28
28
15kV Air
Typical
Capacitance
at 1MHz
VC
8kV Contact
/PUF
(Note 4)
(V)
BU"
BU"
BU"
(V)
<100
Clamp (V)
<110
<110
<140
(pF)
<100
BU"
BU"
BU"
<100
/05&4
1. For applications of 18VDCPSMFTT)JHIFSWPMUBHFTBWBJMBCMFDPOUBDUZPVS-JUUFMGVTF4BMFT3FQSFTFOUBUJWF
2. Tested with IEC-61000-4-2 Human Body Model (HBM) discharge test circuit.
%JSFDUEJTDIBSHFUPEFWJDFUFSNJOBMT*&$QSFGFSSFEUFTUNFUIPE
4. Corona discharge through air (represents actual ESD event).
$BQBDJUBODFNBZCFDVTUPNJ[FEDPOUBDUZPVS-JUUFMGVTF4BMFT3FQSFTFOUBUJWF
6. Leakage current ratings are at 18 VDCBOEμA maximum.
Nominal Voltage Stability to Multiple ESD Impulses
(8kV Contact Discharges per IEC 61000-4-2)
Peak Current and Energy Derating Curve
'PSBQQMJDBUJPOTFYDFFEJOH$BNCJFOUUFNQFSBUVSFUIF
peak surge current and energy ratings must be reduced as
shown below.
NOMINAL VOLTAGE AT 1mADC
30
PERCENT OF RATED VALUE
100
80
60
25
20
15
10
5
40
0
10
1
20
0
-55
Figure 1
50
60
70
80
90
100
110
120
1000
10000
CURRENT (A)
130 140 150
AMBIENT TEMPERATURE ( oC)
Impedance (Z) vs Frequency Typical Characteristic
100
Standby Current at Normalized Varistor Voltage and
Temperature
-0402
-0603
10
-0805
IMPEDANCE (Z)
1.2
NORMALIZED VARISTOR VOLTAGE (V)
100
Figure 2
1.0
0.8
-1206
1
0.1
25O
0.6
85O
0.01
0.4
10
Figure 4
125O
0.2
100
1000
10000
FREQUENCY (MHz)
0.0
0.0001
Figure 3
MLE Varistor Series
0.001
0.01
0.1
1
CURRENT (mA)
32
Revision: July 16, 2009
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/MLE.html for current information.
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > MLE Series
Device Characteristics
Clamping Voltage Over Temperature (VC at 10A)
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 model (approaching 106Ω at its
maximum rated working voltage). Leakage currents at
maximum rated voltage are below 100μ"UZQJDBMMZμA;
GPSTJ[FCFMPXμ"UZQJDBMMZμA.
CLAMPING VOLTAGE (V)
100
V26MLA1206
Typical Temperature Dependance of the Haracteristic
$VSWFJOUIF-FBLBHF3FHJPO
V5.5MLA1206
-40
Figure 6
-20
0
20
40
60
80
TEMPERATURE ( oC)
100
120
140
MLE Series
10
-60
VNOM VALUE AT 25 oC (%)
SUPPRESSOR VOLTAGE IN PERCENT OF
100%
Energy Absorption/Peak Current Capability
25
10%
1E -9
o
50o 75o
1E -8
1E -7
Figure 5
Energy dissipated within the MLE is calculated by
multiplying the clamping voltage, transient current
and transient duration. An important advantage of the
multilayer is its interdigitated electrode construction within
the mass of dielectric material. This results in excellent
current distribution and the peak temperature per energy
absorbed is very low. The matrix of semiconducting grains
combine to absorb and distribute transient energy (heat)
TFF4QFFEPG3FTQPOTF
5IJTESBNBUJDBMMZSFEVDFTQFBL
temperature; thermal stresses and enhances device
reliability.
100o 125 oC
1E -6
1E -5
1E -4
1E -3
1E -2
SUPPRESSOR CURRENT (ADC)
Speed of Response
The Multilayer Suppressor is a leadless device. Its
response time is not limited by the parasitic lead
inductances found in other surface mount packages.
The response time of the ZN0EJFMFDUSJDNBUFSJBMJTMFTT
than 1ns and the MLE can clamp very fast dV/dT events
such as ESD. Additionally, in "real world" applications,
the associated circuit wiring is often the greatest
factor effecting speed of response. Therefore, transient
suppressor placement within a circuit can be considered
important in certain instances.
As a measure of the device capability in energy and peak
current handling, the V26MLA1206A part was tested with
NVMUJQMFQVMTFTBUJUTQFBLDVSSFOUSBUJOH"μs). At
the end of the test, 10,000 pulses later, the device voltage
characteristics are still well within specification.
3FQFUJUJWF1VMTF$BQBCJMJUZ
Multilayer Internal Construction
100
PEAK CURRENT = 150A
8/20 s DURATION, 30s BETWEEN PULSES
FIRED CERAMIC
DIELECTRIC
VOLTAGE
V26MLA1206
METAL
ELECTRODES
METAL END
TERMINATION
DEPLETION
10
REGION
0
Figure 8
DEPLETION
2000
4000
6000
8000
10000
12000
NUMBER OF PULSES
REGION
Figure 7
GRAINS
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/MLE.html for current information.
33
Revision: July 16, 2009
MLE Varistor Series
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > MLE Series
Lead (Pb) Soldering Recommendations
The principal techniques used for the soldering of
DPNQPOFOUTJOTVSGBDFNPVOUUFDIOPMPHZBSF*33FnPX
and Wave soldering. Typical profiles are shown on the right.
Reflow Solder Profile
The recommended solder for the MLE suppressor is
B4O1C"H
4O1C
PS4O1C
-JUUFMGVTFBMTPSFDPNNFOETBO3."TPMEFSnVY
230
Wave soldering is the most strenuous of the processes.
To avoid the possibility of generating stresses due to
thermal shock, a preheat stage in the soldering process
is recommended, and the peak temperature of the solder
process should be rigidly controlled.
When using a reflow process, care should be taken to
ensure that the MLE chip is not subjected to a thermal
gradient steeper than 4 degrees per second; the ideal
gradient being 2 degrees per second. During the soldering
process, preheating to within 100 degrees of the solder's
QFBLUFNQFSBUVSFJTFTTFOUJBMUPNJOJNJ[FUIFSNBMTIPDL
Figure 9
Wave Solder Profile
0ODFUIFTPMEFSJOHQSPDFTTIBTCFFODPNQMFUFEJUJT
still necessary to ensure that any further thermal shocks
BSFBWPJEFE0OFQPTTJCMFDBVTFPGUIFSNBMTIPDLJTIPU
printed circuit boards being removed from the solder
process and subjected to cleaning solvents at room
temperature. The boards must be allowed to cool gradually
UPMFTTUIBO$CFGPSFDMFBOJOH
Figure 10
Lead–free (Pb-free) Soldering Recommendations
Littelfuse offers the Nickel Barrier Termination finish for the
optimum Lead–free solder performance.
Lead–free Re-flow Profile
5IFQSFGFSSFETPMEFSJT4O"H$V
XJUIBO3."
flux, but there is a wide selection of pastes and fluxes
available with which the Nickel Barrier parts should be
compatible.
MAXIMUM TEMPERATURE 260˚C
20 - 40 SECONDS WITHIN 5˚C
RAMP RATE
<3˚C/s
The reflow profile must be constrained by the maximums
JOUIF-FBEoGSFF3FnPX1SPmMF'PS-FBEoGSFF8BWF
TPMEFSJOHUIF8BWF4PMEFS1SPmMFTUJMMBQQMJFT
PREHEAT ZONE
/PUFUIF-FBEoGSFFQBTUFnVYBOEQSPmMFXFSFVTFEGPS
evaluation purposes by Littelfuse, based upon industry
standards and practices. There are multiple choices of all
three available, it is advised that the customer explores the
optimum combination for their process as processes vary
considerably from site to site.
MLE Varistor Series
60 - 150 SEC
> 217˚C
5.0
6.0
7.0
Figure 11
34
Revision: July 16, 2009
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/MLE.html for current information.
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > MLE Series
Product Dimensions (mm)
1"%-":065%&.&/4*0/4
$)*1-":065%*.&/4*0/4
C
E
B
NOTE
D
L
A
/PUF"WPJENFUBMSVOTJOUIJTBSFBQBSUTBSF
not recommended for use in applications using
Silver (Ag) epoxy paste.
Dimension
A
1206 Size
0805 Size
0603 Size
0402 Size
IN
MM
IN
MM
IN
MM
IN
MM
0.160
4.06
0.120
0.100
B
0.020
C
0.040
1.02
0.040
1.02
0.89
0.024
0.61
D (max.)
1.80
1.10
1.00
L
0.012
W
0.024
0.006
0.004
0.004
0.60
E
0.040
0.008
0.006
0.006
0.008
0.008
Part Numbering System
V 18 MLE 1206 X X X
PACKING OPTIONS (see Packaging section for quantities)
T: 13in (330mm) Diameter Reel, Plastic Carrier Tape
H: 7in (178mm) Diameter Reel, Plastic Carrier Tape
R: 7in (178mm) Diameter Reel, Paper Carrier Tape
DEVICE FAMILY
Littelfuse TVSS Device
MAXIMUM DC
WORKING VOLTAGE
END TERMINATION OPTION
N: Nickel Barrier (Ni/Sn)
MULTILAYER SERIES
DESIGNATOR
CAPACITANCE OPTION
No Letter: Standard
L: Low Capacitance Version
DEVICE SIZE:
i.e., 120 mil x 60 mil
(3mm x 1.5mm)
Packaging*
Quantity
Device Size
13” Inch Reel
'T' Option)
7” Inch Reel
('H' Option)
7” Inch Reel
('R' Option)
Bulk Pack
('A' Option)
1206
10,000
N/A
10,000
N/A
10,000
4,000
0402
N/A
N/A
10,000
N/A
1BDLBHJOH
*UJTSFDPNNFOEFEUIBUQBSUTCFLFQUJOUIFTFBMFECBHQSPWJEFEBOEUIBUQBSUTCFVTFEBTTPPOBTQPTTJCMFXIFOSFNPWFEGSPNCBHT
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/MLE.html for current information.
35
Revision: July 16, 2009
MLE Varistor Series
MLE Series
W
NOTE: Avoid metal runs in this area.
Varistor Products
Surface Mount Multilayer Varistors (MLVs) > MLE Series
Tape and Reel Specifications
D0
PRODUCT
IDENTIFYING
LABEL
P0
For T and H Pack Options: PLASTIC CARRIER TAPE
For R Pack Options: EMBOSSED PAPER CARRIER TAPE
P2
E
F
K0
W
B0
t1
D1
P1
Symbol
EMBOSSMENT
TOP TAPE
A0
178mm
OR 330mm
DIA. REEL
8mm
NOMINAL
Dimensions in Millimeters
Description
0402 Size
0603, 0805 & 1206 Sizes
A0
Width of Cavity
%FQFOEFOUPO$IJQ4J[FUP.JOJNJ[F3PUBUJPO
B0
Length of Cavity
%FQFOEFOUPO$IJQ4J[FUP.JOJNJ[F3PUBUJPO
%FQFOEFOUPO$IJQ4J[FUP.JOJNJ[F3PUBUJPO
K0
Depth of Cavity
W
Width of Tape
F
Distance Between Drive Hole Centers and Cavity Centers
E
Distance Between Drive Hole Centers and Tape Edge
P1
Distance Between Cavity Centers
P2
Axial Drive Distance Between Drive Hole Centers & Cavity Centers
P0
Axial Drive Distance Between Drive Hole Centers
D0
Drive Hole Diameter
D1
%JBNFUFSPG$BWJUZ1JFSDJOH
T1
Top Tape Thickness
N/A
0.1 Max
0.1 Max
/PUFT
t$POGPSNTUP&*"3FWJTJPO"
t$BOCFTVQQMJFEUP*&$QVCMJDBUJPO
MLE Varistor Series
36
Revision: July 16, 2009
©2009 Littelfuse, Inc.
Specifications are subject to change without notice.
Please refer to www.littelfuse.com/series/MLE.html for current information.