General Purpose Surface
Mounted Resistors
WCR Series
Welwyn Components
Excellent reliability
Wide range of sizes and ohmic values
Wrap around terminations
Inner electrode protection
Electrical Data
0201
Power rating @ 70C
Resistance range
Limiting element votage
TCR*
Resistance Tolerance
Standard values
Ambient temperature range
Zero-ohm Jumper Chip Rating
Zero-ohm Jumper Chip Resistance
watts
ohms
volts
ppm/C
%
C
amps
milliohms
0402
0603
0805
0.125
150
100
1
E24 or E96
-55 to 125
1.5
<50
1206
1210
2010
0.5
200
200
2512
1.0
0.1
0.05
0.063
10R to 1M0
25
50
250
0.25
0.25
1R0 to 10M
0.5
1
2
Physical Data
Dimensions (mm)
Style
0201
0402
0603
0805
1206
1210
2010
2512
* Notes – TCR for low values 1R to 10R: -400 to +600ppm/ºC, 11R to 100R: ±200ppm/ºC
TCR for high values 3M3 to 10M: ±300ppm/º
L
T
C
W
0.6 ± 0.03
0.23 ± 0.03
0.12 ± 0.05
0.3 ± 0.03
1.0 ± 0.05
0.35 ± 0.05
0.2 ± 0.1
0.5 ± 0.03
1.6 ± 0.15
0.5 ± 0.15
0.25 ± 0.2
0.8 ± 0.15
2.0 ± 0.2
0.5 + 0.15 -0.10
0.4 ± 0.2
1.25+ 0.2 -0.1
3.2 +0.1 -0.25 1.6 + 0.1 -0.15 0.55 +0.15 -0.1 0.5 + 0.2-0.25
3.2 + 0.1 -0.2
0.55 +0.15 -0.1
0.5 ± 0.25
2.6 ± 0.15
5.0 ± 0.15
0.56 ± 0.15
0.60 ± 0.25
2.5 ± 0.15
6.3 ± 0.15
0.56 ± 0.15
0.60 ± 0.25
3.2 ± 0.15
A
0.15 ± 0.05
0.25 ± 0.1
0.25 ± 0.2
0.4 ± 0.2
0.5+ 0.2 -0.25
0.5 ± 0.2
0.60 ± 0.25
0.60 ± 0.25
C
T
A
L
A
W
Wrap-around terminations
(3 faces)
Construction
The chips have a high alumina substrate (96% minimum) with
a ruthenium oxide resistance element and silver palladium,
nickel and tin plated terminations. A glazed protection coat
is applied to the resistive element (See Fig.1)
Figure 1
Tin Plating
Nickel Barrier
Dipped Conductor
Silver
Palladium
Epoxy Melamine
Protection
Glass Dielectric
Resistance Element
Terminations
Solderability
Strength
The terminations meet the requirements of
IEC 115-1, Clause 4.17.3.2.
The terminations meet requirements of
IEC 68.2.21.
96% min Alumina Substrate
General Note
Welwyn Components reserves the right to make changes in product specification without notice or liability.
All information is subject to Welwyn’s own data and is considered accurate at time of going to print.
A subsidiary of
TT electronics plc
Iss 07.03
© Welwyn Components Limited
· Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
General Purpose Surface
Mounted Resistors
WCR Series
Marking
All resistors are individually marked with 3 digits. The first two
digits are the significant figures and the third defines the
number of added zeros. Jumpers are marked 000. Types 0201
and 0402 have no marking.
E96 1% components that can not be marked with 4 digits
will be marked with a standard 3 digit code. Details can be
supplied upon request.
Table 1
Resistance
value ohms
100R
>100R, 10K
>10K, 100K
>100K, 1M0
>1M0
Welwyn Components
Noise
dB
-10
0
+15
+20
+30
Solvent Resistance
The protective epoxy lacquer and marking are resistant to all
normal industrial cleaning fluids suitable for printed circuits.
Performance Data
Maximum Change
0201
Load: 1000 hrs at 70°C
Shelf life: 12 months at room temp.
Derate linearly to zero from 70°C
Short term overload (6.25 x rated power)
Max voltage
Climatic
Climatic Catagory
Long term damp heat
Temperature rapid change
Resistance to solder heat
Vibration and bump
Noise
Insulation resistance
Voltage proof
ohms
volts
100
500
500
>100K : 2
0402
>100K : 2
0.2
2
100
3
0603
>100K : 2
0.2
2.5
100
3
0805
>100K : 2
0.2
2.5
200
3
55/125/56
1
1
2.5
1
1
2.5
1
1
2.5
1
1
2.5
1
see table 1
> 1G
500
500
500
500
1
2.5
1
1
2.5
1
1
2.5
1
1
2.5
1
1206
>100K : 2
0.2
2.5
400
3
1210
2010
2512
3% + 0.1R
0.2
5
400
3
R%
10R-100K : 1 4R7-100K : 1 1R-100K : 1 1R-100K : 1 1R-100K : 1
R%
R%
volts
0.2
2
50
3
1R-100K : 1 1R-100K : 1
>100K : 2
>100K : 2
0.2
2.5
400
3
0.2
2.5
400
3
zero @ 125 °C
R%
R%
R%
R%
R%
All chips are tape mounted and supplied on standard 8mm
All chips are tape mounted and supplied on standard 8mm
tape reel, as IEC publication 286-3.
tape reel, as IEC publication 286-3.
180mm (7 inch) reel is standard
180mm (7 inch) reel is standard carries 5,000 pieces.
250mm (10 inch) reel carrying double the standard quantity
(Except 0402 carries 10,000 pieces)
can be supplied by agreement.
Packaging
Packaging
Chip Resistor Labstock For Designers
Chip Resistor Labstock For Designers
WCR chip resistors are available in a special package of the most
WCR chip resistors are available in a special package of the most
popular sizes containing 50 each of the E24 values.
popular sizes containing 50 each of the E24 values.
Please contact the sales desk for full details of this excellent
Please contact the sales desk for full details of this excellent
solution for designers and your prototype build requirements.
Note: For zero ohm jumper chips use the dummy value & tolerance code
R005J
© Welwyn Components Limited
Bedlington, Northumberland NE22 7AA, UK
Telephone: +44 (0) 1670 822181 · Facsimile: +44 (0) 1670 829465 · Email: info@welwyn-tt.com · Website: www.welwyn-tt.com
Issue D ·
02.09
07.03
