Temperature Derating Curve
125
Ambient Temperature /°C
% of Rated Power
75
50
25
0
100
5510751 -
Pulse Withstanding
Chip Resistors
PWC Series
© 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
Thermal Performance Data
07. 08
Packaging
0805 and 1206 PWC series resistors are
supplied on 8mm carrier tape and 7 inch
reels as per IEC 286-3, quantity per
reel; 3000.
2010 and 2512 PWC series resistors are
supplied on 12mm carrier tape and 7
inch reels as per IEC 286-3, quantity per
reel; 2010 : 3000pcs; 2512 : 1800pcs.
Reels of 1000pcs are available on
request.
PWC resistors are ideally suited for handling by automatic
methods due to their rectangular shape and the small
dimensional tolerances. Electrical connection to a ceramic
substrate or to a printed circuit board can be made by reflow
or wave soldering of wrap-around terminations.
Wrap-around terminations provide good leach properties and
ensure reliable contact. Due to the robust construction, the
PWC can be immersed in the solder bath for 30 seconds at
260°C. This enables the resistor to be mounted on one side
of a printed circuit board and wire-leaded components
applied on the other side.
PWC resistors themselves can operate at a maximum
temperature of 155°C. For soldered resistors, the joint
temperature should not exceed 110°C. This condition is met
when the stated power levels at 70°C and recommended pad
and trace areas are used. Allowance should be made if
smaller areas of copper are used.
A full Application Note on the PWC Series is available.
Ordering Procedure
Specify type reference etc as shown in this example of
PWC2512 10K ohms 1%.
Temperature Rise Curves
80
Power Dissipation /W
Temperature Rise /°C
60
40
20
0
0 0.5 1 1.5
0805
1206
2010
2512
Application Notes
2.5 ± 0.5
13 ± 0.5
33 ± 1.0
Marking
0.8 ± 0.15
80 ± 2
178 ± 2
9.0
8mm tape: 9mm ± 0.5
12mm tape: 13mm ± 0.5
+ 0.1
- 0.15
P1
A0
B0
D1
D0
P0
P2
G F
W
E
T2
T1
K0
T
Tape dimensions in mm
W P1 P0 P2 D0 D1 E F A0 B0 K0 T T1 T2
±0.3 ±0.1 ±0.1 ±0.05 ±0.1 ±0.2 ±0.1 ±0.05 ±0.1 ±0.1 ±0.1 ±0.05 nom ±0.15
0805 8 4 4 2 1.5 1 1.75 3.5 1.65 2.45 0.8 0.2 0.05 1.1
1206 8 4 4 2 1.5 1 1.75 3.5 1.95 3.55 1.0 0.2 0.05 1.3
2010 12 4 4 2 1.5 1.5 1.75 5.5 2.79 5.89 0.91 0.28 0.06 1.21
2512 12 8 4 2 1.5 1.5 1.75 5.5 3.61 6.96 1.17 0.28 0.06 1.45
Type PWC 2512 - 10K F
Size
Value (use IEC62 code)
Tolerance (use IEC62 code)
D 0.5%
F 1%
J 5%