Document Number: 63001

For any questions, contact: foil@vishay.com

www.vishay.com

Revision: 20-Nov-07

3

S Series

High Precision Foil Resistor with TCR of ± 2.0 ppm/°C,

Tolerance of ± 0.005 % and Load Life Stability of ± 0.005 %

Vishay Foil Resistors

FIGURE 3 - POWER DERATING CURVE

200 %

175 %

150 %

125 %

100 %

75 %

50 %

25 %

0

- 75

- 50

- 25

0

+ 25

+ 50

+ 75

+ 100 + 125 + 150 + 175 + 200

Ambient Temperature (

°C)

- 55 °C

+ 70 °C

Double Rated Power

Rated Power

∆

Safe operation

for < 150 ppm

R after 2000

hours load-life.

FIGURE 4 - TRIMMING TO VALUES

(Conceptual Illustration)

Mutual Inductance

Reduction due

to Change in

Current Direction

Current Path

Before Trimming

Note: Foil shown in black, etched spaces in white

Interloop Capacitance

Reduction in Series

Trimming Process

Removes this Material

from Shorting Strip Area

Changing Current Path

and Increasing

Resistance

Current Path

After Trimming

TABLE 3 - ENVIRONMENTAL PERFORMANCE COMPARISON

MIL-PRF-55182

CHAR J

S-SERIES

MAXIMUM

ΔR

S-SERIES

TYPICAL

ΔR

Test Group I

Thermal shock, 5 x (- 65 °C to + 150 °C)

± 0.2 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Short time overload, 6.25 x rated power

± 0.2 %

± 0.01 % (100 ppm)

± 0.003 % (30 ppm)

Test Group II

Resistance temperature characteristics

± 25 ppm/°C

± 4.5 ppm/°C

± 2.0 ppm/°C

Characteristic

Low temperature storage (24 h at - 65 °C)

± 0.15 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Low temperature operation

(45 min, rated power at - 65 °C)

± 0.15 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Terminal strength

± 0.2 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Test Group III

DWV

± 0.15 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Resistance to solder heat

± 0.1 %

± 0.01 % (100 ppm)

± 0.005 % (50 ppm)

Moisture resistance

± 0.4 %

± 0.05 % (500 ppm)

± 0.01 % (100 ppm)

Test Group IV

Shock

± 0.2 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Vibration

± 0.2 %

± 0.01 % (100 ppm)

± 0.002 % (20 ppm)

Test Group V

Life test at 0.3 W/+ 125 °C

2000 h

± 0.5 %

± 0.015 % (150 ppm)

± 0.01 % (100 ppm)

10 000 h

± 2.0 %

± 0.05 % (500 ppm)

± 0.03 % (300 ppm)

Test Group Va

Life test at 0.6 W (2 x rated power)/+ 70 °C, 2000 h

± 0.5 %

± 0.015 % (150 ppm)

± 0.01 % (100 ppm)

Test Group VI

High temperature exposure (2000 h at + 175 °C)

± 2.0 %

± 0.1 % (1000 ppm)

± 0.05 % (500 ppm)

Test Group VII

Voltage coefficient

5 ppm/V

< 0.1 ppm/V

< 0.1 ppm/V