RTO 50
www.vishay.com
Vishay Sfernice
50 W Power Resistor, Thick Film Technology, TO-220
FEATURES
• 50 W at 25 °C heatsink mounted
• Adjusted by sand trimming
• Leaded or surface mount versions
• High power to size ratio
• Non inductive element
DESIGN SUPPORT TOOLS
• Material categorization: for definitions of compliance
please see www.vishay.com/doc?99912
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Models
Available
Because of the knowledge and experience in Thick Film technology, Vishay Sfernice has been able to develop a high power
resistor in a TO-220 package called RTO 50. The special design of this component allows the dissipation of 50 W when mounted
on a heatsink.
DIMENSIONS in millimeters
RTO 50F - LEADED
RTO 50C - FOR SURFACE MOUNTING
4.5
4.5
10.1
Ø 3.6
12.5
10.1
1.3
15
Ø 3.6
12.5
8.8
1.3
15
8.8
2
3
13.7
0.3
1.6
5.08
Ø 0.8
2.5
• Only for RTO 50 version C = during surface mount soldering, the
soldering temperature profile must not cause the metal tab of this
device to exceed 220 °C.
5.08
STANDARD ELECTRICAL SPECIFICATIONS
MODEL
SIZE
RTO 50
Note
(1) E24 series
TO-220
RESISTANCE RATED POWER
RANGE
P25 °C
W
0.010 to 550K (1)
50
LIMITING ELEMENT
VOLTAGE UL
V
500
TOLERANCE
±%
1, 2, 5, 10
TEMPERATURE
COEFFICIENT
± ppm/°C
150
MECHANICAL SPECIFICATIONS
TECHNICAL SPECIFICATIONS
Mechanical Protection
Resistive Element
Connections
Weight
Dissipation and Associated
Molded
Thick film
Tinned copper alloy
2.2 g max.
ENVIRONMENTAL SPECIFICATIONS
Temperature Range
Climatic Category
Sealing
Flammability
-55 °C to 155 °C
55 / 155 / 156
Sealed container, solder immersion
IEC 60695-11-5,
2 applications 30 s separated by 60 s
Note
• Not compatible with RoHS reflow profile
Revision: 17-Oct-2018
CRITICAL
RESISTANCE
5K
Onto a heatsink
Thermal Resistance
and Nominal Power
50 W at +25 °C
RTH (j - c): 2.6 °C/W
Free air: 2.25 W at +25 °C
Dielectric Strength
MIL STD 202 (301)
2000 VRMS - 1 min
10 mA max.
Insulation Resistance
106 M
Inductance
0.1 μH
DIMENSIONS
Standard Package
TO-220 insulated case
Document Number: 50035
1
For technical questions, contact: sferfixedresistors@vishay.com
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
RTO 50
www.vishay.com
Vishay Sfernice
PERFORMANCE
TESTS
CONDITIONS
REQUIREMENTS
EN 60115-1
2 Pr 5 s for R < 2
1.6 Pr 5 s for R 2
US < 1.5 UL
± (0.25 % + 0.05 )
EN 60115-1
60 068-2-14
5 cycles -55 °C to +155 °C
± (0.5 % + 0.05 )
EN 60115-1
Pr at +25 °C, 1000 h CEI 115_1
± (1 % + 0.05 )
EN 60115-1
56 days RH 95 %
± (0.5 % + 0.05 )
Vibration
MIL STD 202
method 204 C test D
± (0.2 % + 0.05 )
Terminal Strength
MIL STD 202
method 211 test A1
± (0.2 % + 0.05 )
Momentary Overload
Rapid Temperature Change
Load Life
Humidity (Steady State)
RESISTANCE VALUE IN RELATION TO TOLERANCE AND TCR
0.01
Resistance Values
0.015
Tolerances
Temperature Coefficient
(-55 °C to +155 °C)
0.1
0.5
± 250 ppm/°C
± 150 ppm/°C
± 1 % at ± 10 %
Standard
± 900 ppm/°C
± 700 ppm/°C
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:
1
T
P = ------------------------------------------------------------------------------------------R TH (j - c) + R TH (c - h) + R TH (h - a)
P:
T:
RTH (j - c):
RTH (c - h):
RTH (h - a):
Expressed in W
Difference between maximum working temperature and room temperature
Thermal resistance value measured between resistive layer and outer side of the resistor. It is
the thermal resistance of the component: (Special Features Table)
Thermal resistance value measured between outer side of the resistor and upper side of the
heatsink. This is the thermal resistance of the interface (grease, thermal pad), and the quality of
the fastening device
Thermal resistance of the heatsink
Example:
RTH (c - a): For RTO 50 power rating 13 W at ambient temperature +30 °C
Thermal resistance RTH (j - c): 2.6 °C/W
Considering equation (1) we have:
T 155 °C - 30 °C = 125 °C
T
P
125
13
RTH (j - c) + RTH (c - h) + RTH (h - a) = ------- = -------- = 9.6 °C/W
RTH (c - a) + RTH (h - a) 9 .6 °C/W - 2.6 °C/W 7 °C/W
Revision: 17-Oct-2018
Document Number: 50035
2
For technical questions, contact: sferfixedresistors@vishay.com
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
RTO 50
www.vishay.com
Vishay Sfernice
OVERLOADS
POWER RATING
The applied voltage must always be lower than the
maximum overload voltage of 750 V.
The values indicated on the graph below are applicable to
resistors in air or mounted onto a heatsink.
The temperature of the heatsink 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.
MARKING
Model, style, resistance value (in ), tolerance (in %),
manufacturing date, Vishay Sfernice trademark.
RATED POWER IN %
ENERGY CURVE
100
ENERGY IN JOULES
100
10
1
80
60
40
20
0.1
0
0
25
0.01
0.001
10-7
50
100
150
200
HEATSINK TEMPERATURE IN °C
10-6
10-5
10-4
10-3
10-2
10-1
OVERLOAD DURATION IN s
PACKAGING
Tube of 50 units
POWER CURVE
POWER IN W
100 000
10 000
1000
100
10-7
10-6
10-5
10-4
10-3
10-2
10-1
OVERLOAD DURATION IN s
Revision: 17-Oct-2018
Document Number: 50035
3
For technical questions, contact: sferfixedresistors@vishay.com
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
RTO 50
www.vishay.com
Vishay Sfernice
ORDERING INFORMATION
RTO
50
F
100K
± 1%
XXX
TU50
e1
MODEL
STYLE
CONNECTIONS
RESISTANCE VALUE
TOLERANCE
CUSTOM DESIGN
optional
on request:
special TCR,
shape, etc.
PACKAGING
LEAD (Pb)-FREE
± 1%
± 2%
± 5%
± 10%
F: radial leads
C: surface mount
GLOBAL PART NUMBER INFORMATION
R
T
O
0
5
0
F
R
6
8
0
0
J
T
E
1
GLOBAL
MODEL
SIZE
LEADS
OHMIC VALUE
TOLERANCE
PACKAGING
RTO
050
F = radial leads
C = surface mount
The first four digits are significant
figures and the last digit
specifies the number of zeros
to follow.
R designates decimal point.
48R70 = 48.7
48701 = 48 700
10002 = 100 000
R0100 = 0.01
R6800 = 0.68
27000 = 2700 = 2.7 k
F=1%
G=2%
J=5%
K = 10 %
T = tube
Size 30 and 50:
tube 50 pieces
RELATED DOCUMENTS
APPLICATION NOTES
Potentiometers and Trimmers
www.vishay.com/doc?51001
Guidelines for Vishay Sfernice Resistive and Inductive Components
www.vishay.com/doc?52029
Revision: 17-Oct-2018
Document Number: 50035
4
For technical questions, contact: sferfixedresistors@vishay.com
THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT
ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc?91000
Legal Disclaimer Notice
www.vishay.com
Vishay
Disclaimer
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Revision: 01-Jan-2023
1
Document Number: 91000