Power Metal Strip® Resistors,
Low Value (down to 0.001 Ω), Surface Mount, 4-Terminal
www.vishay.com For technical questions, contact: ww2bresistors@vishay.com Document Number: 30108
20 Revision: 01-Jul-09
WSK
Vishay Dale
FEATURES
•4-Terminal design allows for 1 % tolerance down
to 0.001 Ω and 0.5 % tolerance down to 0.003 Ω
•Ideal for all types of precision current sensing,
voltage division and pulse applications
including switching and linear power supplies,
instruments, power amplifiers
•Proprietary processing technique produces
extremely low resistance values (down to
0.001 Ω)
•All welded construction
•Solderable terminations
•Solid metal Nickel-Chrome or Manganese-Copper alloy
resistive element with low TCR (< 20 ppm/°C)
•Very low inductance 0.5 nH to 5 nH
•Excellent frequency response to 50 MHz
•Compliant to RoHS directive 2002/95/EC
Note
• Part Marking: DALE, Value, Tolerance; due to resistor size limitations some resistance values will be marked with only the resistance value
* Pb containing terminations are not RoHS compliant, exemptions may apply
** Please see document “Vishay Material Category Policy”: www.vishay.com/doc?99902
STANDARD ELECTRICAL SPECIFICATIONS
GLOBAL
MODEL
POWER RATING
P70 °C
W
RESISTANCE RANGE
Ω
± 0.5 % ± 1.0 %
WSK2512 1.0 0.003 to 0.025 0.001 to 0.025
TECHNICAL SPECIFICATIONS
PARAMETER UNIT WSK2512
Temperature Coefficient ppm/°C
0.001 Ω to 0.0029 Ω = ± 250
0.003 Ω to 0.0049 Ω = ± 75
0.005 Ω to 0.025 Ω = ± 35
Operating Temperature Range °C - 65 to + 170
Maximum Working Voltage V (P x R)1/2
Weight/1000 pieces g 63.6
GLOBAL PART NUMBER INFORMATION
NEW GLOBAL PART NUMBERING: WSK25125L000FTA (PREFERRED PART NUMBERING FORMAT)
GLOBAL MODEL RESISTANCE VALUE TOLERANCE CODE PACKAGING CODE SPECIAL
WSK2512 L = mΩ*
R = Decimal
5L000 = 0.005 Ω
R0100 = 0.01 Ω
* Use “L” for resistance
values < 0.01 Ω
D = ± 0.5 %
F = ± 1.0 %
EA = Lead (Pb)-free, tape/reel
EK = Lead (Pb)-free, bulk
TA = Tin/lead, tape/reel (R86)
BA = Tin/lead, bulk (B43)
(Dash Number)
(Up to 2 digits)
From 1 to 99 as
applicable
HISTORICAL PART NUMBERING: WSK2512 0.005 Ω 1 % R86 (WILL CONTINUE TO BE ACCEPTED)
WSK2512 0.005 Ω 1 % R86
HISTORICAL MODEL RESISTANCE VALUE TOLERANCE CODE PACKAGING
K251 5L02WS T0 FA0
Document Number: 30108 For technical questions, contact: ww2bresistors@vishay.com www.vishay.com
Revision: 01-Jul-09 21
WSK
Power Metal Strip® Resistors,
Low Value (down to 0.001 Ω), Surface Mount, 4-Terminal Vishay Dale
DIMENSIONS
Note
• Embossed carrier tape per EIA-481-1A
L W
H
T
A
B
l
a
e
b d c
MODEL
DIMENSIONS in inches [millimeters]
RESISTANCE
RANGE
Ω
LWH T A B
WSK2512
0.001 to 0.0049 0.250 ± 0.010
[6.35 ± 0.254]
0.125 ± 0.010
[3.18 ± 0.254]
0.025 ± 0.010
[0.635 ± 0.254]
0.087 ± 0.010
[2.21 ± 0.254]
0.030 ± 0.010
[0.762 ± 0.254]
0.020 ± 0.010
[0.508 ± 0.254]
0.005 to 0.025 0.250 ± 0.010
[6.35 ± 0.254]
0.125 ± 0.010
[3.18 ± 0.254]
0.025 ± 0.010
[0.635 ± 0.254]
0.047 ± 0.010
[1.19 ± 0.254]
0.030 ± 0.010
[0.762 ± 0.254]
0.020 ± 0.010
[0.508 ± 0.254]
MODEL SOLDER PAD DIMENSIONS in inches [millimeters]
abcde I
WSK2512 0.125 [3.18] 0.130 [3.30] 0.030 [0.76] 0.020 [0.51] 0.055 [1.40] 0.065 [1.65]
PERFORMANCE
TEST CONDITIONS OF TEST TEST LIMITS
Thermal Shock - 55 °C to + 150 °C, 1000 cycles, 15 min at each extreme ± (0.5 % + 0.0005 Ω) ΔR
Short Time Overload 5 x power for 5 s ± (0.5 % + 0.0005 Ω) ΔR
Low Temperature Storage - 65 °C for 24 h ± (0.5 % + 0.0005 Ω) ΔR
High Temperature Exposure 1000 h at + 170 °C ± (1.0 % + 0.0005 Ω) ΔR
Bias Humidity + 85 °C, 85 % RH, 10 % Bias, 1000 h ± (0.5 % + 0.0005 Ω) ΔR
Mechanical Shock 100 g’s for 6 ms, 5 pulses ± (0.5 % + 0.0005 Ω) ΔR
Vibration Frequency varied 10 Hz to 2000 Hz in 1 min, 3 directions, 12 h ± (0.5 % + 0.0005 Ω) ΔR
Load Life 1000 h at rated power, + 70 °C, 1.5 h “ON”, 0.5 h “OFF” ± (1.0 % + 0.0005 Ω) ΔR
Resistance to Solder Heat + 260 °C Solder, 10 s to 12 s dwell, 25 mm/s emergence ± (0.5 % + 0.0005 Ω) ΔR
Moisture Resistance MIL-STD-202 Method 106, 0 % power, 7a and 7b not required ± (0.5 % + 0.0005 Ω) ΔR
PACKAG ING
MODEL REEL
TAPE WIDTH DIAMETER RIECES/REEL CODE
WSK2512 12 mm/Embossed Plastic 178 mm/7" 2000 R86
70
0
Derating
- 65 - 55 - 25 0 25 50 75 100 125 150 170
Ambient Temperature °C
20
40
60
80
100
120
Rated Power in %
Document Number: 91000 www.vishay.com
Revision: 18-Jul-08 1
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