IM
PR
OVED
PRODUCT
Bulk Metal
®
Foil Technology High Precision 4-Terminal Power
Current Sensing Resistors with TCR as low as ± 1 ppm/°C
Maximum,
Tolerance ± 0.1 %
and Rise Time 1.0 ns Effectively No Ringing
VCS331, VCS332
Vishay Foil Resistors
Document Number: 63153 For any questions, contact: foil@vishaypg.com www.foilresistors.com
Revision: 29-Mar-10 1
INTRODUCTION
The VCS331 and VCS332 offer precision Bulk Metal
®
Foil
technology resistors as low as 0.25 with a temperature
coefficient down to 1 ppm/°C maximum and unmatched long
term stability. The 4 terminal current sensing resistors, when
mounted on a heat sink, can sustain 10 W continuously
without an appreciable change in resistance (0.15 %
maximum). The typical 50 % power derating specification
associated with other technologies is not necessary. A
choice of lead configurations is available.
Our application engineering department is available to
advise and make recommendations. For non-standard
technical requirements and special applications, please
contact us.
FEATURES
Temperature coefficient of resistance (TCR):
down to ± 1 ppm/°C max. (see table 2)
Tolerance: to ± 0.1 % (see table 1)
Power rating (heat-sinked): 10 W
Load life stability: ± 0.01 % (100 ppm) at 25 °C,
2000 h at rated power
Resistance range: 0.25 to 500
Vishay Foil resistors are not restricted to standard
values; specific “as required” values can be supplied
at no extra cost or delivery (e.g. 1R2345 vs. 1R)
Electrostatic discharge (ESD) up to 25 000 V
Non-inductive, non-capacitive design
Rise time: 1.0 ns effectively no ringing
Current noise: 0.010 µV
RMS
/V of applied voltage (< - 40 dB)
Thermal EMF: 0.05 µV/°C typical
Voltage coefficient: < 0.1 ppm/V
Non-inductive: 0.08 µH
Non hot spot design
Thermal stabilization time < 1 s (nominal value achieved
within 10 ppm of steady state value)
Terminal finish: lead (Pb)-free or tin/lead alloy
Prototype quantities available in just 5 working days
or sooner. For more information, please contact
foil@vishaypg.com
For better performances, please contact application
engineering
Notes
(1)
Tighter tolerance is available - for more details contact application engineering
(2)
The lower of the two limitations (power or current) is decisive
(3)
Heatsink - aluminum (6" length x 4" width x 2" height x 0.04" thick)
* Pb containing materials are not RoHS compliant, exemptions may apply
TABLE 1 - CHARACTERISTICS
MODEL NUMBER RESISTANCE RANGE BEST TOLERANCE
(1)
POWER RATING
(2)
at + 25 °C
MAXIMUM CURRENT
(2)
VCS331, VCS332 0.25 < R < 500 ± 0.1 %
10 W on heat sink
(3)
or 3 W in free air
5 A
TABLE 2 - TCR CHART (maximum)
(0 °C TO + 60 °C)
0.25 to < 1 ± 3 ppm/°C
1 to < 10 ± 2 ppm/°C
10 to < 500 ± 1 ppm/°C
FIGURE 1 - POWER DERATING CURVE
(Further Derating Not Necessary)
+ 100
+ 75
+ 50
+ 25
0
Ambient Temperature °C
Percent of
Rated Power
- 55 °C + 25 °C
- 50
+ 50
0
+ 100
+ 150 + 200
