Approval Sheet
WM07B_Q, WM04B_Q, WM07C_Q,
WM04C_Q
±
1%,
±
0.5%,
±
0.25%,
±
0.1%
TC50 , TC25
High Precision Thin Film MELF Resistors
Size: 0207, 0204
AEC-Q200 Compliant
*Contents in this sheet are subject to change without prior notice.
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ASC_WMxxB&C_Q
JUL - 2018
Approval Sheet
FEATURE
1. SMD enabled structure thin film resistor
2. High reliability and stability of
±0.3%
and below per customer request
3. High precision of TCR: 50 & 25 ppm/°C and below per customer request
4. Best in class pulse load capability
5. RoHS compliant and lead free
6. AEC-Q200 Compliant
APPLICATION
•
•
•
•
Medical equipment
Measuring instrument
Communication device
Power / Meter Converter
DESCRIPTION
A uniform alloy film is deposited on a high grade ceramic body (Al2O3) and achieved the desired temperature coefficient by
annealing. Nickel plated termination caps are firmly attached on the ceramic body. It is achieved the target value by
smoothly cutting a helical groove in the resistive layer without damaging the ceramic body. The resistive film is covered by
epoxy molding compound designed for electrical, mechanical and climatic protection. For environmental soldering issue,
Nickel plated terminations receive a final pure tin on it. Four color code rings designate the resistance value in accordance
with IEC 60062.
Fig 1. Construction of MELF
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ASC_WMxxB&C_Q
JUL - 2018
Approval Sheet
QUICK REFERENCE DATA
Item
Series No.
Size code
Resistance Tolerance
Resistance Range
TCR (ppm/°C)
Max. dissipation at T
amb
=70°C
Max. Operating Voltage (DC or RMS)
Max. Overload Voltage (DC or RMS)
Operating temperature
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
0.2
~1M
WM07B_Q
General Specification
WM07C_Q
WM04B_Q
WM04C_Q
0207 ( 6123 )
0204 ( 3715 )
±1%, ±0.5%, ±0.25%, ±0.1%
10Ω~1MΩ
±25ppm/C
1/2W
300V
600V
- 55 ~ +155
℃
0.2
~1M
10Ω~1MΩ
±25ppm/C
1/4W
200V
400V
±50ppm/C
±50ppm/C
RCWV
=
Rated Power
×
Resistance Value
or Max. RCWV listed above, whichever is lower.
DIMENSIONS:( unit:mm)
Type
L
D
K
Weight (g)
1000pcs
0207
5.90±0.20
±
2.20±0.10
±
1.40±0.10
±
87.81
0204
3.50±0.10
±
1.40±0.15
±
0.90±0.10
±
22.34
K
L
D
Page 3 of 12
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JUL - 2018
Approval Sheet
MARKING & RESISTANCE RANGE / TOLERANCE
Standard Resistance Values
±1%、±0.5%、±0.25%、±0.1%
E192
100
101
102
104
105
106
107
109
110
111
113
114
115
117
118
120
121
123
124
126
127
129
130
132
133
135
137
138
140
142
143
145
147
149
150
152
154
156
158
160
162
164
165
167
169
174
178
180
182
184
187
189
191
193
196
198
200
203
205
208
210
213
215
218
221
223
226
229
232
234
237
240
243
246
249
252
255
258
261
264
267
271
274
277
280
284
287
291
294
298
301
305
309
312
316
320
324
328
332
336
340
344
348
352
357
361
365
370
374
379
383
388
392
397
402
407
412
417
422
427
432
437
442
448
453
459
464
470
475
481
487
493
499
505
511
517
523
530
536
542
549
556
562
569
576
583
590
597
604
612
619
626
634
642
649
657
665
673
681
690
698
706
715
723
732
741
750
759
768
777
787
796
806
816
825
835
845
856
866
876
887
898
909
920
931
942
953
965
976
988
Color 1
Coding
Color 2
Coding
0
Color 3
Coding
0
1
2
3
4
5
6
7
8
9
Color 4
Coding
10
10
10
10
10
10
0
1
2
3
4
5
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
10
10
-1
-2
Resistance values more than two digiting tags (<1R) or more than three digiting tags (>1R) will not
provide marking.
Page 4 of 12
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Approval Sheet
FUNCTIONAL DESCRIPTION
Product characterization
Standard values of nominal resistance are taken from the E192 series for resistors with a tolerance of
±1%,
±0.5%, ±0.25%, ±0.1%.
The values of the E192 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.
Cylindrical placement can be on ceramic rods and printed-circuit boards (PCBs).
Electrical connection to the circuit is by individual soldering condition.
The end terminations guarantee a reliable contact.
RECOMMEND LAND PATTERN
B
C
A
Type
A (mm)
B (mm)
C (mm)
0207
3.0
1.7
2.4
0204
1.6
1.2
1.6
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ASC_WMxxB&C_Q
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