LTO 30
Vishay Sfernice
30 Watt Power Resistor Thick Film Technology
FEATURES
• 30 Watt at 25 °C Case Temperature Heatsink
Mounted
• Direct mounting ceramic on heatsink
• Broad Resistance Range: R010 to 550K
• Non Inductive
• TO-220 package: Compact and easy to mount
LTO series are the extension of RTO types. We used the direct
ceramic mounting design (no metal tab) of our RCH power
resistors applied to semiconductor packages.
• RoHS compliant
• Isolated case
RoHS
COMPLIANT
DIMENSIONS
in millimeters
10.4
3.2
3.2
Ø3.2
16.2
1.3
3.5
12.7
0.8
0.6
5.08
1.8
• Tolerance unless otherwise specified: ± 0.3 mm
MECHANICAL SPECIFICATIONS
Mechanical Protection
Resistive Element
Substrate
Connections
Weight
Mounting Torque
Molded
Thick Film
Alumina
Tinned Copper
2 g max.
1N-m
ELECTRICAL SPECIFICATIONS
Resistance Range
Tolerances (Standard)
Dissipation and Associated
Power Rating
and Thermal Resistance
of the component
Temperature Coefficient
0.010
Ω
to 550 kΩ
± 1 % to ± 10 %
Onto a heatsink
30 W at + 25 °C (case temperature)
R
TH
(j-c): 4.2 °C/W
free air:
2.25 W at + 25 °C
See Performance table
± 150 ppm/°C
250 V
1500 V
RMS
- 1 minute - 10 mA max.
≥
10
4
MΩ
≤
0.1 µH
2.08 kΩ
DIMENSIONS
Standard Package
TO-220
Isolated case
Dielectric Strength
MIL STD 202
Insulation Resistance
Inductance
Critical Resistance
Standard
Limiting Element Voltage
ENVIRONMENTAL SPECIFICATIONS
Temperature Range
Climatic Category
- 55 °C to + 150 °C
55/155/56
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For technical questions, contact sfer@vishay.com
Document Number: 50049
Revision 30-May-06
LTO 30
30 Watt Power Resistor Thick Film Technology
PERFORMANCE
TESTS
Momentary Overload
CONDITIONS
EN 60115-1
1.5 Pr/5 s
Us < 1.5 UL
EN 60115-1
IERC 60068-2-14 Tests Na
5 cycles
- 55 °C to + 155 °C
EN 60115-1
1000 h Pr at + 25 °C
MIL STD 202
Method 103 B Cond. D
MIL STD 202
Method 204 Cond. D
MIL STD 202
Method 211 Cond. A1
100G, MIL STD 202
Method 213 Cond. I
TYPICAL DRIFTS
± (0.5 % + 0.005
Ω)
Vishay Sfernice
Rapid Temperature Change
± (0.5 % + 0.005
Ω)
Load Life
± (1 % + 0.005
Ω)
± (0.5 % + 0.005
Ω)
± (0.2 % + 0.005
Ω)
± (0.2 % + 0.005
Ω)
± (0.5 % + 0.005
Ω)
Humidity (Steady State)
Vibration
Terminal Strength
Shock
SPECIAL FEATURES
Resistance Values
Tolerances
Typical Temperature
Coefficient
(- 55 °C/+ 155 °C)
± 900 ppm/°C
≥
0.010
≥
0.015
± 1 % at ± 10 %
± 700 ppm/°C
± 250 ppm/°C
± 150 ppm/°C
≥
0.1
≥
0.5
CHOICE OF THE HEATSINK
The user must choose according to the working conditions of the component (power, room temperature).
Maximum working temperature must not exceed 155 °C. The dissipated power is simply calculated by the following ratio:
ΔT
[R
TH
(j-c) + R
TH
(c-a)]
P:
ΔT:
expressed in W
difference between maximum working temperature and room temperature.
(1)
P=
R
TH:
(j-c): thermal resistance value measured between resistive layer and outer side of the resistor. It is the thermal
resistance of the component.
R
TH:
(c-a): thermal resistance value measured between outer side of the resistor and room temperature. It is the
thermal resistance of the heatsink itself (type, shape), the quality of the fastening device, and the thermal resistance of the
thermal compound.
Example:
R
TH:
(c-a) for LTO30 power rating 10 W at ambient temperature + 30 °C.
Thermal resistance R
TH
(j-c): 4.2 °C/W
Considering equation (1) we have:
ΔT
= 155 °C - 30 °C = 125 °C
ΔT
125
=
= 12.5 °C/W
R
TH
(j-c) + R
TH
(c-a) =
P
10
R
TH
(c-a) = 12.5 °C/W - 4.2 °C/W = 8.3 °C/W
with a thermal grease R
TH
(c - h) = 1 °C/W, we need a heat sink with R
TH
(h - a) = 7.3 °C/W
Document Number: 50049
Revision 30-May-06
For technical questions, contact sfer@vishay.com
www.vishay.com
15
LTO 30
Vishay Sfernice
OVERLOADS
In any case the applied voltage must be lower than the maximum overload voltage of 375 V.
The values indicated on the graph below are applicable to resistors in air or mounted onto a heatsink.
30 Watt Power Resistor Thick Film Technology
ENERGY CURVE
ENERGY IN JOULES
10
1
0.1
0.01
10
-6
10
-5
10
-4
10
-3
10
-2
OVERLOAD DURATION IN SECONDS
POWER RATING CHART
The temperature of the case should be maintained within the limits specified.
To improve the thermal conductivity, surfaces in contact should be coated with a silicone grease and the torque applied on the
screw for tightening should be around 1 Nm.
100
% RATED POWER
75
50
25
0
0
20
40
60
80
100
120
140
155
CASE TEMPERATURE IN DEGREES CELSIUS
MARKING
Model, Style, Resistance Value (in
Ω),
Tolerance (in %), Manufacturing Date, VISHAY trademark.
PACKAGING
Tube of 50 units
ORDERING INFORMATION
LTO
MODEL
30
STYLE
F
100 kΩ
CONNECTIONS RESISTANCE VALUE
±1%
TOLERANCE
±1%
±2%
±5%
± 10 %
xxx
CUSTOM DESIGN
Optional
on request:
special TCR,
shape etc.
TU50
PACKAGING
e3
LEAD (Pb)-FREE
SAP PART NUMBERING GUIDELINES
L
T
MODEL
O
0
3
0
F
1
0
0
0
2
F
TOL
T
E
3
STYLE CONNECTIONS
SAP Part Number LTO030F10002FTE3
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RESISTANCE
VALUE
PACK LEAD FREE
For technical questions, contact sfer@vishay.com
Document Number: 50049
Revision 30-May-06
Legal Disclaimer Notice
Vishay
Notice
Specifications of the products displayed herein are subject to change without notice. Vishay Intertechnology, Inc.,
or anyone on its behalf, assumes no responsibility or liability for any errors or inaccuracies.
Information contained herein is intended to provide a product description only. No license, express or implied, by
estoppel or otherwise, to any intellectual property rights is granted by this document. Except as provided in Vishay's
terms and conditions of sale for such products, Vishay assumes no liability whatsoever, and disclaims any express
or implied warranty, relating to sale and/or use of Vishay products including liability or warranties relating to fitness
for a particular purpose, merchantability, or infringement of any patent, copyright, or other intellectual property right.
The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications.
Customers using or selling these products for use in such applications do so at their own risk and agree to fully
indemnify Vishay for any damages resulting from such improper use or sale.
Document Number: 91000
Revision: 08-Apr-05
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