Surface Mounted
Resistors
CR Series
Welwyn Components
•
CECC released products
•
Custom designs/sizes available
•
Any resistance value available within specified range
•
Terminations available for wire bonding or soldering
•
Available in sizes down to 0503
•
Resistance range 1 ohm to100M ohms
•
Tolerances down to 0.1%
•
Solder terminations have a nickel barrier layer
•
Shorting Links available
Electrical Data
Commercial
Power rating at 70°C
Resistance range
Limiting element voltage
TCR -55° to +155°C
Resistance tolerance
Ambient temperature range
Approved CECC 40401-004
Power rating at 70°C
Resistance range
Limiting element voltage
TCR -55°C to +125°C
TCR +20°C to +70°C
Resistance tolerance
Ambient temperature range
Approved CECC 40401-008
Power rating at 70°C
Resistance range
Limiting element voltage
TCR -55°C to +155°C
Resistance tolerance
Ambient temperature range
Approved CECC 40401-003
Power rating at 70°C
Resistance range
Limiting element voltage
TCR -55°C to +125°C
Resistance tolerance
Ambient temperature range
Values
Thermal impedance
°C/watt
800
360
watts
ohms
volts
ppm/°C
%
°C
CR0503
0.063
1R to 10M
50
CR0805
0.125
CR1005
CR1206
CR2010
CR2512
0.125
0.25
0.5
1.0
1R to 100M
1R to 1M
100
150
200
400
500
<10 ohms 350: 10 to 100 ohms 200:
100 to 1M ohm 100: >1M ohm 250
0.1, 0.25, 0.5, 1, 2, 5
-55 to 155
CR1206
0.25
1R to 10M
100
200
<10 ohms 200: 10 to 1M 100: >1M 200
<10 ohms 200: 10 to 1M 50: >1M 100
0.5, 1, 2, 5
-55 to +125
CR0805
CR1206
CR2010
0.125
0.25
0.5
1R to 10M
1R to 10M 1R to 1M
100
200
400
<10 ohms 200: 10 to 1M ohms 100:
>1M ohms 250
0.1, 0.25, 0.5, 1, 2, 5
-55 to 155
CR0805
CR1206
0.063
0.125
1R to 3M
1R to 5M
100
200
<5 ohms 500: 5 to 10 ohms 350:
10 to 3M ohms 100: >3M ohms 250
0.25, 0.5, 1, 2, 5
-55 to 125
E24 & E96 preferred
290
200
80
70
CR2512
1.0
1R to 1M
500
Notes
See table of value ranges
watts
ohms
volts
ppm/°C
ppm/°C
%
°C
CR0805
0.125
See table of value ranges
watts
ohms
volts
ppm/°C
%
°C
See table of value ranges
watts
ohms
volts
ppm/°C
%
°C
See table of value ranges
Any value to order
Mounted on custom
designed PCB’s
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
Issue E · 08.04
© 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
17
Surface Mounted
Resistors
CR Series
Welwyn Components
Physical Data
Dimensions of Standard Styles (mm) & Weight (g)
Wrap around
Style
0503
0805
1005
1206
2010
2512
†
L
W
T max
0.5
0.6
0.7
0.7
0.7
0.7
A
B
†
C
0.20±0.1
0.3±0.1
0.4±0.15
0.4±0.15
N/A
N/A
Wt
0.005
0.009
0.015
0.020
0.036
0.055
Alternative styles for
surface mounting resistors
A
B
L
A
W
T
1.25±0.2 0.63±.15
2.0±0.2 1.25±0.15
2.5±0.3 1.25±0.2
3.2±0.2
5.1±0.3
6.5±0.3
1.6±0.2
2.5±0.2
3.2±0.2
Not available
0.3±0.15 0.9 min
Not available
0.4±0.2
0.6±0.3
0.6±0.3
1.7 min
3.0 min
4.4 min
C
C
T
Wrap-around terminations
(3 faces)
L
W
Planar terminations
This dimension determines the number of conductors which may pass under the surface mounted device.
Construction
Thick film resistor material, overglaze and organic protection
are screen printed on a 96% alumina substrate.
Solderability
Wrap-around terminations have an electroplated nickel barrier
and solder coating, this ensures excellent ‘leach’ resistance
properties and solderability. They will withstand immersion in
solder at 260°C for 30 seconds.
Terminations
Planar (or single-sided) termination is gold and suitable for
wire-bonding; wrap-around is suitable for soldering.
Marking
All relevant information recorded on the primary package or reel.
Performance Data
CECC 40401-008 CECC40401-004 CECC40401-003
Requirements
Load at rated power: 1000 hours at 70°C
Shelf life: 12 months at room temp.
Derating from rated power at 70°C
Overload
Dry Heat: 1000 hours at UCT
(125°C for 003 & 004 - 155°C for 008)
Long term damp heat
Temperature rapid change
Resistance to solder heat
Voltage proof
∆R%
∆R%
∆R%
volts
2
0.5
0.5
0805 : 200
2010 : 400
2
0.5
0.5
1206 : 300
2512 : 500
∆R%
∆R%
∆R%
2
-
Zero at 155°C
∆R%
0805:1 1206:0.5
2
Requirements
2
-
Zero at 125°C
0.5
1
Requirements
≤
3M3 2
>3M3 3
-
Zero at 125°C
2
≤
3M3 2
>3M3 3
2
1
2
1
to 10M 1
>10M 2
1
0.25
0.25
0503 : 100
All others : 500
0.1
0.2
>10M 1
0.25
0.05
0.05
0.1
0.02
Maximum
2
Actual
Typical
0.25
Note: An 0.01 ohm addition to be added to the performance of all resistors <10 ohms
Value Ranges (ohms)
Tolerance
Size
0503
0805
1005
1206
2010
2512
5
1 to 10M
1 to 100M
1 to 100M
1 to 100M
1 to 1M
1 to 1M
2
1 to 10M
1 to 50M
1 to 50M
1 to 50M
1 to 1M
1 to 1M
1
10 to 10M
1 to 20M
1 to 20M
1 to 25M
1 to 1M
1 to 1M
%
0.5
100 to 1M
10 to 10M
10 to 10M
10 to 10M
10 to 10M
10 to 10M
0.25
N/A
100 to 1M
100 to 1M
100 to 1M
100 to 1M
100 to 1M
0.1
N/A
100 to 1M
100 to 1M
100 to 1M
N/A
N/A
© 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
18
Issue E · 08.04
Surface Mounted
Resistors
CR Series
Welwyn Components
Application Notes
Operating Temperature Range
The chips themselves can operate at a maximum temperature
of 155°C (see performance claims above). For soldered chips,
the joint temperature should not exceed 110°C. This
condition is met when the stated power levels at 70°C are
used.
Packaging
Wrap-around Termination
Chip resistors are supplied taped and reeled on standard
8mm tape to IEC 286-3.
Quantity per reel; 3000 max.
Mounting
This chip resistor is ideally suited for handling by automatic
methods due to its rectangular shape and the small
dimensional tolerances. Electrical connection to a ceramic
substrate or to a printed circuit board can be made by wire
bonding (eg suffix ‘G’ in CR0805G) or by reflow soldering of
wrap-around terminations (eg suffix ‘F’ in CR0805F).
The ‘F’ terminations provide good leach properties and ensure
reliable contact. Due to the robust construction the resistor
chip 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 other wire-leaded components
on the other side.
Planar Terminations
Resistor chips are supplied in waffle packs.
Ordering Procedure
Specify type reference, value and tolerance as shown in this example of CR0805 10M 0.1%:
Type
Resistance value
(IEC62 code)
Tolerance
(IEC62 code)
B
C
D
0.1%
2%
5%
CR0805
10M
B
© 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 E · 08.04
19
