RCMA
Vishay Sfernice Molded Metal Film Very High Stability (< 0.25 % after 1000 h)
and Precision (up to 0.1 %) Resistors
www.vishay.com For technical questions, contact: sfer@vishay.com Document Number: 52009
172 Revision: 05-Oct-09
POWER RATING
TEMPERATURE RISE
PRACTICAL OPERATING TOLERANCES
Table 2 and 3 show the basic characteristics and maximum
values under different stresses. In fact, the values and drifts
are maintained to within narrower limits.
So, in operation under the specified conditions (Pr at 70 °C)
the total drift (load life + TCR) of a RCMA K4 does not exceed
± 0.25 %.
SPECIAL APPLICATIONS
Temperature coefficient tracking to 5 ppm/°C.
Tolerance matching to 0.05 %.
Selection of positive or negative TCR in temperature range
of - 20 °C to + 125 °C.
For these applications and other requirements consult
Vishay Sfernice.
MARKING
Printed: Vishay Sfernice trademark, series, style (due to lack
of space RCMA02 is printed MA02), ohmic value (in Ω),
tolerance (in %), temperature coefficient, manufacturing
date.
PERFORMANCE
CECC 40 100 EN 140-201 TYPICAL VALUES
AND DRIFTS
TESTS CONDITIONS STD 202 REQUIREMENTS
Load Life at
Maximum Category Temperature 1000 h at 125 °C 50 % of Pn
≤ ± 1 %
Insulation resistance > 1 GΩ± 0.25 % or 0.05 Ω
Short Time Overload 2.5 Um/5 s
limited to 2 Un
≤ ± (0.25 % + 0.05 Ω) ± 0.1 % or 0.05 Ω
Damp Heat Humidity
(Steady State)
56 days
with low load
≤ ± (1 % + 0.05 Ω)
Insulation resistance > 1 GΩ± 0.2 % or 0.05 Ω
Rapid Temperature Change - 55 °C + 155 °C ≤ ± (0.25 % + 0.05 Ω) ± 0.1 % or 0.05 Ω
Climatic Sequence - 65 °C + 155 °C ≤ ± (1 % + 0.05 Ω)
Insulation resistance > 1 GΩ
± 0.25 % or 0.05 Ω
Insulation resistance 106 MΩ
Terminal Strength Pull - twist - 2 bends ≤ ± (0.25 % + 0.05 Ω) ± 0.05 % or 0.05 Ω
Vibration 10 Hz to 500 Hz ≤ ± (0.25 % + 0.05 Ω) ± 0.05 % or 0.05 Ω
Soldering (Thermal Shock) + 260 °C 10 s ≤ ± (0.25 % + 0.05 Ω) ± 0.05 % or 0.05 Ω
Load Life Cycle 90’/30’
1000 h at Pn at 70 °C
≤ ± (1 % + 0.05 Ω)
Insulation resistance > 1 GΩ± 0.1 % or 0.05 Ω
Shelf Life 1 year
ambient temperature - ± 0.1 % or 0.05 Ω
AMBIENT TEMPERATURE IN °C
RATED POWER IN %
100
50
0
050 70 100 125 150
30
RATED POWER IN W
HOT SPOT TEMPERATURE IN °C
40
30
20
10
00 1 1.5
RCMA1
RCMA2
RCMA4
20.5
50
Temperature coefficient
between - 10 °C and + 70 °C
K5 ≤ ± 10 ppm/°C
K4 ≤ ± 15 ppm/°C
LONG LIFE
90’/30’ cycles
ambient temperature 70 °C
1000 h at Pr± 0.05 %
10 000 h at Pr± 0.15 %