Document Number: 50035

Revision 14-Jan-05

www.vishay.com

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RTO 50

Vishay Sfernice

For technical questions, contact sfer@vishay.com

PERFORMANCE

TESTS

CONDITIONS

TYPICAL DRIFTS

NF EN 140000

Momentary Overload

2Pr/5s

± (0.25% + 0.05Ω)

Us < 1.5UL

NF EN 140000

Rapid Temperature Change

CEI 68214 Tests Na

± (0.5% + 0.05Ω)

5 cycles - 55°C to + 155°C

Load Life

NF EN 140000 Pr at + 25°C CEI 115_1

± (1% + 0.05Ω)

Humidity (Steady State)

MIL STD 202

± (0.5% + 0.05Ω)

Method 103 B Cond. D

Vibration

MIL STD 202

± (0.2% + 0.05Ω)

Method 204 Cond. D

Terminal Strength

MIL STD 202

± (0.2% + 0.05Ω)

Method 211 Cond. A1

Power Resistor Thick Film Technology

Resistance Values

≥ 0.010Ω

≥ 0.015Ω

≥ 0.1Ω

≥ 0.5Ω

Tolerances

± 1% at ± 10%

Standard

± 900ppm/°C

± 700ppm/°C

± 250ppm/°C

± 150ppm/°C

Temperature

Coefficient

SPECIAL FEATURES

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:

P =

∆T

(1)

P:

expressed in W

T:

difference between maximum working temperature and room temperature.

(j-c):

thermal resistance value measured between resistive layer and outer side of the resistor. It is the thermal

resistance of the component: (Special Features Table)

(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) and the quality of the fastening device.

Example:

Considering equation (1) we have:

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

=

= 9.6°C/W

∆T

P

125

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