LTO-50 datasheet(2/5 Pages) VISHAY

2 / 5 page

LTO 50

www.vishay.com

Vishay Sfernice

Revision: 09-Dec-15

Document Number: 50050

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

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 150 °C. The dissipated power is simply calculated by the following ratio:

P: Expressed in W

ΔT: Difference between maximum working temperature and room

temperature

RTH (j - c): Thermal resistance value measured between resistive layer

and outer side of the resistor. It is the thermal resistance of the

component.

RTH (c - h): 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.

RTH (h - a): Thermal resistance of the heatsink.

Example:

RTH (c - a) for LTO 50 power rating 10 W at ambient temperature +25 °C

Thermal resistance RTH (j - c): 2.5 °C/W

Considering equation (1) we have:

ΔT = 150 °C - 25 °C = 125 °C

RTH (j - c) + RTH (c - h) + RTH (h - a) =

= 12.5 °C/W

RTH (c - h) + RTH (h - a) = 12.5 °C/W - 2.5 °C/W = 10 °C/W

with a thermal grease RTH (c - h) = 1 °C/W, we need a heatsink with RTH (h - a) = 9 °C/W.

PERFORMANCE

TESTS

CONDITIONS

REQUIREMENTS

Momentary Overload

EN 60115-1

1.5 Pr / 5 s

US < 1.5 UL

± (0.5 % + 0.005

Ω)

Rapid Temperature Change

EN 60115-1

IEC 60068-2-14 Test Na

5 cycles

-55 °C to +155 °C

± (0.5 % + 0.005

Ω)

Load Life

EN 60115-1

1000 h Pr at +25 °C

± (1 % + 0.005

Ω)

Humidity (Steady State)

MIL-STD-202

method 103 B cond. D

± (0.5 % + 0.005

Ω)

Vibration

MIL-STD-202

method 204 cond. D

± (0.2 % + 0.005

Ω)

Terminal Strength

MIL-STD-202

method 211 cond. A1

± (0.2 % + 0.005

Ω)

Shock

100G, MIL-STD-202

method 213 cond. I

± (0.5 % + 0.005

Ω)

SPECIAL FEATURES

Resistance Values

≥ 0.010

≥ 0.015

≥ 0.1

≥ 0.5

Tolerances

± 1 % at ± 10 %

Typical Temperature Coefficient

(-55 ° to +155 °C)

± 900 ppm/°C

± 700 ppm/°C

± 250 ppm/°C

± 150 ppm/°C

ΔT

TH (j - c)

TH (c - h)

TH (h - a)

-------------------------------------------------------------------------------------------

()

ΔT

------

125

--------

LTO-50 Datasheet(PDF) 2 Page - Vishay Siliconix

LTO-50 Datasheet(HTML) 2 Page - Vishay Siliconix

Html Pages

1 2 3 4 5

Datasheet Download

Link URL