Approval sheet
WW12C, WW08C, WW06C, WW04C,
WW02C
±
5%,
±
1%,
±
0.5%
Low ohm chip resistors ( power )
Size 1206, 0805, 0603, 0402, 0201
*Contents in this sheet are subject to change without prior notice.
Page 1 of 8
ASC_WWxxC_V05
Mar.-2012
Approval sheet
FEATURE
1. High power rating and low range
2. High reliability and stability
3. Suitable for current sensing of small mobile devices
4. RoHS compliant & Lead free
5. Up side down mounting to minimize resistance drift after soldering
APPLICATION
•
•
•
•
•
•
Game equipment
Mobile phone
Battery pack
Power supply
DSC
HDD
DESCRIPTION
The resistors are constructed in a high grade ceramic body (aluminum oxide). Internal metal electrodes are
added at each end and connected by a resistive paste that is applied to the top surface of the substrate. The
composition of the paste is adjusted to give the approximate resistance required and the value is trimmed to
nominated value within tolerance which controlled by laser trimming of this resistive layer.
The resistive layer is covered with a protective coat. Finally, the two external end terminations are added. For
ease of soldering the outer layer of these end terminations is a Tin (lead free) alloy.
Fig 1. Construction of Chip-R
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ASC_WWxxC_V05
Mar.-2012
Approval sheet
QUICK REFERENCE DATA
Item
Series No.
Size code
Resistance Tolerance
Resistance Range
TCR (ppm/°C)
0.015Ω ~ 0.019Ω
0.020Ω ~ 0.030Ω
0.033Ω ~ 0.050Ω
0.051Ω ~ 0.100Ω
Max. dissipation at
T
amb
=70°C
Max. Operation Current
(DC or RMS)
Climatic category
(IEC 60068)
Note :
1.
This is the maximum current that may be continuously supplied to the resistor element, see “IEC publication
60115-8”
Max. Operation current : So called RCWC (Rated Continuous Working Current) is determined by
±150
ppm
±100
ppm
±100
ppm
±100
ppm
1/2W
2.2 ~ 5.7A
±200
ppm
±200
ppm
±100
ppm
±100
ppm
1/3 W
1.14 ~ 4.7 A
N/A
0 ~ +350 ppm
0 ~ +250 ppm
±150
ppm
1/4 W
1.58 ~ 3.54 A
55/125/56
N/A
±350
ppm
±300
ppm
±100
ppm
1/8 W
1.1 ~ 2.5 A
N/A
±500
ppm
±300
ppm
±100
ppm
1/10 W
1.0 ~ 2.2 A
0.015Ω ~ 0.100Ω
0.015Ω ~ 0.100Ω
General Specification
WW12C
1206 (3216)
WW08C
0805 ( 2012 )
WW06C
0603 ( 1608 )
±5%, ±1%, ±0.5%
0.020Ω ~ 0.100Ω
0.020Ω ~ 0.100Ω
0.020Ω ~ 0.100Ω
WW04C
0402 ( 1005 )
WW02C
0201 ( 0603 )
( E24 +E96 )
( E24 +E96 )
( E24 +E96 )
( E24 +E96 )
( E24 +E96 )
2.
RCWC
=
Rated Power / Resistance Value
MECHANICAL DATA(unit: mm)
Symbol
L
W
H
WW12C
3.10
±
0.20
1.60
±
0.15
0.60
±
0.10
0.50
±
0.25
0.60
±
0.20
WW08C
2.00
±
0.15
1.25
±
0.10
0.60
±
0.10
0.40
±
0.20
0.40
±
0.20
WW06C
1.60
±
0.10
0.80
+0.15
-0.05
0.50
±
0.10
0.30
±
0.10
0.30
±
0.10
WW04C
1.00
±
0.05
0.50
±
0.15
0.35
+0.05
-0.10
0.25
+0.05
-0.10
0.25
+0.05
-0.10
WW02C
0.60
±
0.03
0.30
±
0.03
0.23
±
0.03
0.15
±
0.05
0.15
±
0.05
c
d
L
c
c
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ASC_WWxxC_V05
Mar.-2012
Approval sheet
MARKING
Each resistor is marked with a three-digit code on the substrate to designate the nominal resistance value.
Please refer below table list!
0402 and 0201 sizes are no marking!
Example:
R10 = 0.100Ω
050 = 0.050Ω
FUNCTIONAL DESCRIPTION
Product characterization
Standard values of nominal resistance are taken from the E96 & E24 series for resistors with a tolerance of
±5%
&
±1%.
The values of the E24/E96 series are in accordance with “IEC publication 60063”.
De-rating curve
The power that the resistor can dissipate depends on the operating temperature; see Fig.2
MOUNTING
Due to their rectangular shapes and small tolerances, Surface Mountable Resistors are suitable for handling by
automatic placement systems.
Chip placement can be on ceramic substrates and printed-circuit boards (PCBs).
Electrical connection to the circuit is by individual soldering condition.
The end terminations guarantee a reliable contact.
Resistive layer is on the bottom side as below !
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ASC_WWxxC_V05
Mar.-2012
Approval sheet
SOLDERING CONDITION
The robust construction of chip resistors allows
them to be completely immersed in a solder bath
of 260°C for 10 seconds. Therefore, it is possible
to mount Surface Mount Resistors on one side of
a PCB and other discrete components on the
reverse (mixed PCBs).
Surface Mount Resistors are tested for
solderability at 245°C during 3 seconds within
lead-free solder bath. The test condition for no
leaching is 260°C for 30 seconds. Typical
examples of soldering processes that provide
reliable joints without any damage are given in
Fig 3.
Fig 3. Infrared soldering profile for chip resistor
CATALOGUE NUMBERS
The resistors have a catalogue number starting with .
WW04
Size code
WW02 : 0201
WW04 : 0402
WW06 : 0603
WW08 : 0805
WW12 : 1206
C
Type code
0201, 1/10W
0402, 1/8W
0603, 1/4W
0805, 1/3W
1206, 1/2W
R050
Resistance code
E96 +E24:
R is first digit followed by 3
significant digits.
0.020Ω = R020
0.100Ω = R100
0.025Ω = R025
F
Tolerance
J :
±5%
F :
±1%
D :
±0.5%
T
Packaging code
T : 7” Reel taping
A : 7” Reel taping
15Kpcs/reel
L
Termination code
L
=
Sn base
(lead free)
Reeled tape packaging
Reeled tape packaging
Reeled tape packaging
Reeled tape packaging
Reeled tape packaging
WW02C: 8mm width paper taping 2mm pitch, 15,000pcs per reel.
WW04C: 8mm width paper taping 2mm pitch, 10,000pcs per reel.
WW06C: 8mm width paper taping 4mm pitch, 5,000pcs per reel.
WW08C: 8mm width paper taping 4mm pitch, 5,000pcs per reel.
WW12C: 8mm width paper taping 4mm pitch, 5,000pcs per reel.
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ASC_WWxxC_V05
Mar.-2012