Walsin Technology Corporation
Page 1 of 7 WR04X Version 13 Nov.-2006
WR04X
±1%, ±5%
General purpose chip resistors
Size 0402
Customer :
Approval No :
Issue Date :
Customer Approval :
Walsin Technology Corporation
Page 2 of 7 WR04X Version 13 Nov.-2006
FEATURE
1. Small size and light weight
2. High reliability and stability
3. Reduced size of final equipment
4. Lower assembly costs
5. Higher component and equipment reliability
6. Lead free product is available
APPLICATION
• Mobile phone
• PDA
• Camcorders
• Pagers
• Palmtop computers
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 Lead-tin or Tin (Lead free) alloy.
Fig 1. Consctruction of Chip-R WR04
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Page 3 of 7 WR04X Version 13 Nov.-2006
QUICK REFERENCE DATA
Item General Specification
Series No. WR04
Size code 0402(1005)
Resistance Range 1Ω~10MΩ(±5% tolerance),10Ω~1MΩ(±1% tolerance), Jumper
Resistance Tolerance ±1%
E96/E24
±5%
E24
TCR (ppm/°C)
R≥1MΩ
1MΩ＞R＞10Ω
R≤10Ω
≤ ± 200
-300~+500
-300~+500
≤ ± 200
-300~+500
Max. dissipation @
Tamb=70°C 1/16 W
Max. Operation Voltage
(DC or RMS) 50V
Max. Overload Voltage
(DC or RMS) 100V
Climatic category (IEC
60068) 55/155/56
Note :
1. This is the maximum voltage that may be continuously supplied to the resistor element, see “IEC publication
60115-8”
2. Max. Operation Voltage : So called RCWV (Rated Continuous Working Voltage) is determined by
ValueResistancePower RatedRCWV ×= or Max. RCWV listed above, whichever is lower.
3. For Resistance range 1Ω~10Ω and 1MΩ~10MΩ of tolerance ±1% series No. is WR04W, please refer to
specification respectively.
Dimensions:
WR04X
L 1.00 ± 0.05
W 0.50 ± 0.05
T 0.35 ± 0.05
Tb 0.25 ± 0.10
Tt 0.20 ± 0.10
Protective coat
Resistive layer
End termination
Ceramic Substrate
T
Tb
Tt
T
W
L
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Page 4 of 7 WR04X Version 13 Nov.-2006
MARKING
WR04 has no marking on the product overcoat for both 5% & 1%.
FUNCTIONAL DESCRIPTION
Product characterization
Standard values of nominal resistance are taken from the E24 series for resistors with a tolerance of ±5%,
and E96 series for resistors with a tolerance of ±1%. The values of the E24/E96 series are in accordance
with “IEC publication 60063”
Derating
The power that the resistor can dissipate depends on the operating temperature; see Fig.2
Figure 2. Maximum dissipation in percentage of rated power
As a function of the ambient temperature
CATALOGUE NUMBERS
The resistors have a catalogue number starting with :
WR04 X 3742 J T _
Size code
WR04 : 0402
Type code
X : Normal
W : Out of resistance
range (1% of 1Ω ~
10Ω, 1MΩ~ 10MΩ)
Resistance code
E24 : 2 significant digits
followed by no. of
zeros and a blank
4.7Ω =4R7_
10Ω =100_
220Ω =221_
Jumper =000_
(“_” means a blank)
E96 : 3 significant digits
followed by no. of
zeros
102Ω =1020
37.4KΩ =3742
Tolerance
F : ±1%
J : ±5%
P : Jumper
Packaging code
T : 7” Reeled taping
B : Bulk
Termination code
_ = SnPb base (“_”
means a blank)
L = Sn base (lead
free)
1. Reeled tape packaging : 8mm width paper taping 10,000pcs per reel.
2. Bulk packaging : 10,000pcs per poly-bag
Walsin Technology Corporation
Page 5 of 7 WR04X Version 13 Nov.-2006
MOUNTING
Due to their rectangular shapes and small tolerances, Su rface 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 one minute. 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 60
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 WR04X
TEST CONDITION FOR JUMPER (0 Ω)
Item WR04X
Power Rating At 70°C 1/16W
Resistance MAX. 50mΩ
Rated Current 1A
Peak Current 1.5A
Operating Temperature -55~155°C
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Page 6 of 7 WR04X Version 13 Nov.-2006
TEST AND REQUIREMENTS(JIS C 5201-1 : 1998)
REQUIREMENT
TEST PROCEDURE / TEST METHOD Resistor 0Ω
DC resistance
Clause 4.5
DC resistance values measured at the test voltages specified below :
<10Ω@0.1V, <100Ω@0.3V, <1KΩ@1.0V,
<10KΩ@3V, <100KΩ@10V, <1MΩ@25V, <10MΩ@30V
Within the specified tolerance <50mΩ
Temperature
Coefficient of
Resistance(T.C.R)
Clause 4.8
Natural resistance change per change in degree centigrade.
()
6
121
12 10×
−
−
ttR RR (ppm/°C) t1 : 20°C+5°C-1°C
R1 : Resistance at reference temperature
R2 : Resistance at test temperature
Refer to
“QUICK REFERENCE DATA”
N/a
Short time overload
(S.T.O.L)
Clause 4.13
Permanent resistance change after a 5second application of a voltage
2.5 times RCWV or the maximum overload voltage specified in the
above list, whichever is less.
∆R/R max. ±(2%+0.10Ω) <50mΩ
Resistance to
soldering heat(R.S.H)
Clause 4.18
Un-mounted chips completely immersed for 10±1second in a solder
bath at 270℃±5ºC ΔR/R max. ±(1%+0.05Ω)
no visible damage <50mΩ
Solderability
Clause 4.17
Un-mounted chips completely immersed for 2±0.5second in a solder
bath at 235℃±5℃ 95% coverage min., good tinning and no
visible damage
Leach Test
Clause 4.18
Un-mounted chips completely immersed for 60±1second in a solder
bath at 260℃±5℃ Ditto
Temperature cycling
Clause 4.19
30 minutes at -55°C±3°C, 2~3 minutes at 20°C+5°C-1°C, 30 minutes at
+155°C±3°C, 2~3 minutes at 20°C+5°C-1°C, total 5 continuous cycles ∆R/R max. ±(1%+0.05Ω) < 50mΩ
Damp Heat
(Load life in humidity)
Clause 4.24
1000+48/-0 hours; 1.5hours ON, 0.5hours OFF at RCWV in a humidity
chamber controlled 40±2°C, 90~95% RH
10Ω≤R<1MΩ :
∆R/R max. ±(3%+0.10Ω)
R<10Ω, R≥1MΩ :
∆R/R max. ±(5%+0.10Ω)
< 50mΩ
Load Life (Endurance)
Clause 4.25
1000+48/-0 hours; loaded with Pn or Vmax; 1.5 hours ON, 0.5 hours OFF Ditto.
Bending strength
Clause 4.33
Resistors mounted on a 90mm glass epoxy resin PCB(FR4), bending
once 5mm for 10sec.
No visual damaged,
∆R/R max. ±(1%+0.05Ω) < 50mΩ
Adhesion
Clause 4.32
Pressurizing force: 5N, Test time: 10±1sec. No remarkable damage or removal of the
terminations
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Page 7 of 7 WR04X Version 13 Nov.-2006
PACKAGING
Paper Tape specifications (unit :mm)
Series No. A B W F E
WR04X 1.20±0.10 0.7±0.10 8.00±0.20 3.50±0.05 1.75±0.10
Series No. P1 P0 ΦD T
WR04X 2.00±0.10 4.00±0.10 1.0 0.0
50.1 +
−
Φ 0.40±0.05
Reel dimensions
Symbol A B C D
(unit : mm) Φ178.0±2.0 Φ60.0±1.0 13.0±0.2 9.0±0.5
Taping quantity and Tape material
- Chip resistors 10,000 pcs/reel, Paper tape.
