Approval sheet
WF08P, WF06P
±
1%,
±
5% 0 , 1 ~1M
High Power Chip Resistors
Size 0805 1/4W ; 0603 1/8W
*Contents in this sheet are subject to change without prior notice.
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ASC_WF08-06P_V05
Jul.2010
Approval sheet
FEATURE
1.
2.
3.
4.
5.
Small size and light weight
High reliability and stability
Reduced size of final equipment
High precision
RoHS compliant and Lead free products
APPLICATION
High accuracy dc-power supply
Digital multi-meter
Telecommunication
Computer
Automotive industry
Medical and military equipment
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. Consctruction of Chip-R
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ASC_WF08-06P_V05
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Approval sheet
QUICK REFERENCE DATA
Item
Series No.
Size code
Resistance Tolerance
Resistance Range
TCR (ppm/°C) 20°C ~ +155°C
1Ω ~ 1MΩ
TCR (ppm/°C) 20°C ~
10Ω ~ 1MΩ
1 ~ 10
Max. dissipation at T
amb
=70°C
Max. Operation Voltage (DC or RMS)
Max. Overload Voltage (DC or RMS)
Climatic category (IEC 60068)
Basic specification
Note :
1.
2.
This is the maximum voltage that may be continuously supplied to the resistor element, see “IEC publication
60115-8”
Max. Operation Voltage : So called RCWV (Rated Continuous Working Voltage) is determined by
1/4 W
150V
300V
55/155/56
JIS C 5201-1:1998 / IEC 60068-2-58:2004
- 55°C
≤ ±
100 ppm/°C
≤ ±
150 ppm/°C
1/8W
50V
100V
≤ ±
100 ppm/°C
WF08P
0805 (2012)
±1%, ±5%
0 ,1 ~ 1MΩ (E96+E24 series)
General Specification
WF06P
0603(1608)
RCWV
=
Rated Power
×
Resistance Value
or Max. RCWV listed above, whichever is lower.
3.
0Ω maximum resistance Rmax
≦
15mΩ and rated current (0805)
≦4Amp;(0603) ≦2Amp
DIMENSIONS(unit : mm)
Part No
WF08P
2.00
±
0.10
1.25
±
0.10
0.50
±
0.15
0.40
±
0.20
0.40
±
0.20
WF06P
1.60
±
0.10
0.80
±
0.10
0.45
±
0.15
0.30
±
0.15
0.30
±
0.10
L
W
T
Tb
Tt
MARKING
Each resistor is marked with a three-digit (WF06P ±1%;±5%;WF08P±5%) or four-digit (WF08P ±1%) code on
the protective coating to designate the nominal resistance value.
Example:
01Y = 1Ω (0603 ±1%); 103=10k (0603 ±5%)
1002 = 10kΩ (0805 ±1%); 102=1k (0805 ±5%)
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Approval sheet
FUNCTIONAL DESCRIPTION
Product characterization
Standard values of nominal resistance are taken from the E96&E24 series for resistors with a tolerance of
±1%,±5%.
The values of the E96/E24 series are in accordance with “IEC publication 60063”.
Derating
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.
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 235°C during 2 seconds. 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 Resistors
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Approval sheet
CATALOGUE NUMBERS
The resistors have a catalogue number starting with .
WF08
Size code
WF08: 0805
WF06: 0603
P
Type code
P :Power
0805 size=0.25W
0603 size=0.125W
5% E24:
1002
Resistance code
2 significant digits followed by No.
of zeros
e.g.:
3ohm
10ohm
56Kohm
1% E24+E96:
3 significant digits followed by No.
of zeros
100Ω
37.4KΩ
=1000
=3742
=3R0
=100
=563
F
Tolerance
J :
±5%
F :
±1%
P : Jumper
T
T
Packaging code
: 7” Reeled taping
L
Termination code
L
=
Sn base
(lead free)
paper taping
5Kpcs/reel.
Reeled tape packaging
: 8mm width paper taping 5000pcs per 7” reel.
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Jul.2010
