Pulse Withstanding
Chip Resistors
PWC Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
11.12
· Excellent pulse withstand performance
· Improved working voltage
· Improved power rating
· Standard chip sizes (0805 to 2512)
· Custom designs available
· Anti-sulphur version available
Pulse Withstanding
Chip Resistors
PWC Series
Excellent pulse withstand performance
Improved working voltage
Improved power rating
Standard chip sizes (0805 to 2512)
Custom designs available
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.
© 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
Electrical Data
07. 08
A subsidiary of
TT electronics plc
37
Physical Data
Construction
Thick film resistor material, overglaze and organic protection
are screen printed on a 96% alumina substrate. Wrap-around
terminations have an electroplated nickel barrier and solder
coating, this ensures excellent ‘leach’ resistance properties
and solderability.
Marking
Components are not marked. Reels are marked with type,
value, tolerance, date code and quantity.
Solvent Resistance
The body protection is resistant to all normal industrial
cleaning solvents suitable for printed circuits.
Dimensions of PWC resistors are given below in mm and weight in g
L W T max A B C Wt.
0805Size
Power @70°C W
Resistance range Ohms
Tolerance %
LEV V
TCR ppm/°C
Operating temperature °C
Thermal Impedance °C/W
Pad / trace area *
Values
0.125
150 200 400 500
1R0 to 10M
10R to 1M: 0.5, All values: 1, 5
<10R:200 ≥10R:100
E96 preferred - other values to special order
See graphs – full application note available on request
-55 to +155
0.33 0.5 0.75 1.5 21
220 160 145 80 55 4070
40 50 125 60 100 500250
mm2
1206 2010 2512
2.0±0.3 1.25±0.2 0.6 0.3±0.15 0.9 min 0.3±0.1 0.009
1206
0805
3.2±0.4 1.6±0.2 0.7 0.4±0.2 1.7 min 0.4±0.15 0.020
2010 5.1±0.3 2.5±0.2 0.8 0.6±0.3 3.0 min 0.6±0.25 0.036
2512 6.5±0.3 3.2±0.2 0.8 0.6±0.3 4.4 min 0.6±0.25 0.055
Pulse Capability
T
W
C
A
A
L
B
Wrap-around terminations
(3 faces)
*Recommended minimum pad & adjacent trace area for each termination for rated power dissipation on FR4 PCB
Welwyn Components
Note that anti-sulphur version parts below 100R are
produced in flip-chip format with the resistor element on
the underside.
Pulse Withstanding
Chip Resistors
PWC Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
11.12
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 07. 08
Performance Data
Welwyn Components
Pulse Performance Data
Lightning Surge
lightning surge resistors are tested in
accordance with IEC 60 115-1 using
both 1.2/50µs and 10/700µs pulse shapes.
10 pulses are applied. The limit of
acceptance is a shift in resistance of less
than 1% from the initial value.
Size Maximum Typical
Load at rated power: 1000 hours at 70°C ΔR% 1 0.25
Shelf life test: 12 months at room temperature ΔR% 0.1 0.02
Derating from rated power at 70°C Zero at 155°C
Overload: 6.25 x rated power for 2 seconds ΔR% 1 0.1
Dry heat: 1000 hours at 155°C ΔR% 1 0.2
Long term damp heat ΔR% 1 0.25
Temperature rapid change ΔR% 0.25 0.05
Resistance to solder heat ΔR% 0.25 0.05
Resistance to sulphur-bearing gas (AS version only): ASTM-B-809 0.25 0.05
Voltage proof Volts 500
Note: A 0.01 Ohm addition to be added to the performance of all resistors <10 Ohms.
10
100
1000
10000
1 10100 1000 10000 100000 1000000 10000000
P
e
a
k
v
o
l
t
a
g
e
(
v
o
l
t
s
)
Value (ohms)
1.2/50 s Lightning Surge
O805
1206
2010
2512
10
100
1000
10000
1 10 100 1000 10000 100000 1000000 10000000
Value (ohms)
Peak Voltage (Volts)
O805
1206
2010
2512
Peak Voltage (Volts)
Pulse Withstanding
Chip Resistors
PWC Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
11.12
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 07.08
Pulse Performance Data
Welwyn Components
Single Impulse
The single impulse graph is the result of
50 impulses of rectangular shape
applied at one minute intervals. The
limit of acceptance was a shift in
resistance of less than 1% from the
initial value.
Continuous Load Due to
Repetitive Pulses
The continuous load graph was
obtained by applying repetitive
rectangular pulses where the pulse
period was adjusted so that the average
power dissipated in the resistor was
equal to its rated power at 70°C. Again
the limit of acceptance was a shift in
resistance of less than 1% from the
initial value.
12. 08
Single Pulse
1
10
100
1000
0.0001 0.001 0.01 0.1 1
Pulse Duration ti (s)
Pulse Power P (W)
O805
1206
2010
2512
Continuous Pulses
0.1
1
10
100
0.0001 0.001 0.01 0.1 1
Pulse Duration ti (s)
Puls e Powe r P (W)
O805
1206
2010
2512
Pulse Voltage
10
100
1000
10000
0.0001 0.001 0.01 0.1 1
Pulse Duration ti (s)
Pu lse Voltage (Volts )
O805
1206
2010
2512
Pulse Withstanding
Chip Resistors
PWC Series
www.bitechnologies.com www.irctt.com www.welwyn-tt.com
General Note
TT electronics reserves the right to make changes in product specification without notice or liability.
All information is subject to TT electronics’ own data and is considered accurate at time of going to print.
© TT electronics plc
11.12
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
09. 09
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
Example: PWC2512 at 2.0 kilohms and 5% tolerance
on a reel of 1800 pieces -
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
Type PWC
J
J I
5%
2512 2K0
Size
Termination
Value (use IEC62 code)
Tolerance (use IEC62 code)
Packing
D 0.5%
F 1%
I
T1
Tape Standard
0805, 1206 or 2010 3000/reel
1800/reel
1000/reel
2512
All sizes
Welwyn Components
AS
Standard terminations
Anti-sulphur terminations