CYNTEC CO., LTD.
乾坤科技股½有限公司
DOCUMENT : SM060000NH
REVISION
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: 1 OF 9
1W, 3720, Low Resistance Chip Resistor (Lead free / Halogen Free)
1. Scope
This specification applies to 3.75mm x 2.0mm size 1W, fixed metal film low resistance value chip
resistors rectangular type.
2. Type Designation
RL3720WT –
□□□□
–
□
NH
(1)
(2)
(3) (4)
Where
(1) Type and size
(2) Nominal Resistance value:
Four digits of number
Refer to paragraph 4-1
The“ R
＂shall
be used as a decimal point.
(3) Resistance tolerance:
Refer to paragraph 4-1
(4) NH = Sn plating ( Lead free / Halogen free)
3. Construction and Physical Dimensions
L
a
a
Code
Letter
L
W
W
Dimensions (mm)
3720
2.00
0.20
3.75
0.30
(1 mΩ): 1.0
0.2
(3~12 mΩ): 0.8
0.2
0.40
0.2
0.40
0.2
t
a
d
d
Figure 1. Construction and Dimensions
①
Resistive element : Metal film
(Under protection film)
②
Electrode : Solder Sn (on Cu)
Sn 100% ( Lead free)
③
Protection film : Epoxy resin
④
Substrate : Alumina
t
CYNTEC CO., LTD.
乾坤科技股½有限公司
4. Ratings
4-1 Nominal Resistance Value and Temperature Coefficient of Resistance
Power Rating*
Resistance Value
Resistance Tolerance
Temperature Coefficient of Resistance
0.001
1W
DOCUMENT : SM060000NH
REVISION
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0.003 ~ 0.012
1%(F) ,
2%(G) ,
5%(J)
0~500ppm/℃
±100ppm/℃
4-2 Rated Voltage
The rated voltage shall be determined by the following expression.
V
½
P
R
Where V：Rated voltage (V)
R：Nominal resistance value ()
P：Rated dissipation (W)
4-3 Operating and Storage Temperature Range
-55 to +125℃
5. Marking
Resistance value mark on a top surface use four or three digits by JIS.
White bars are Cyntec internal use only.
Example
0.01Ω
CYNTEC CO., LTD.
乾坤科技股½有限公司
6. Characteristics
Test Item
Short Time Overload
Condition of Test
2.5 * rated power for 5 seconds
Refer to JIS C 5201-1 4.13
DOCUMENT : SM060000NH
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Requirements
R
:
(0.5%+0.0005
)
Without significant damage by
flashover ( spark, arching ), burning
or breakdown etc.
Between Electrode and Protection
Film 100M or over
Between Electrode and Substrate
1,000M or over
Insulation Resistance
The resistor shall be cramped in the
metal block and tested , as shown below.
Test voltage : 100
15V
DC
for 1 minute
Refer to JIS C 5201-1 4.6 Mounting
condition G.
Voltage Proof
The voltage : 100V
AC
(rms.) for 1 minute
R
:
(0.5%+0.0005
)
Refer to JIS C 5201-1 4.7
Without damage by flashover, fire
or breakdown, as shown below.
-55 ~125℃ 5 cycles, 15 min at each
extreme condition
Refer to JIS C 5201-1 4.19
Kept at -55℃, 1,000 hours
Refer to JIS C 5201-1 4.23.4
R
:
(1.0%+0.0005
)
Without distinct damage in
appearance
R
:
(1.0%+0.0005
)
Without distinct damage in
appearance
R
:
(1.0%+0.0005
)
Without distinct damage in
appearance
Uniform coating of solder cover
minimum of 95% surface being
immersed
R
:
(0.5%+0.0005
)
Without distinct deformation in
appearance
Thermal Shock
Low Temperature Storage
High Temperature Exposure
Kept at 125℃ for 1,000 hours
Refer to JIS C 5201-1 4.23.2
Temperature of Solder : 245
5℃
Immersion Duration : 3
0.5 second
Refer to JIS C 5201-1 4.17
Dipped into solder at 270
5℃
for 10
1 seconds
Refer to JIS C 5201-1 4.18
Solderability
Resistance to Soldering Heat
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乾坤科技股½有限公司
Test Item
Load Life
Condition of Test
Rated voltage for 1.5 hours followed by a
pause 0.5 hour at 70
2℃.
Cycle repeated 1000 hours
Refer to JIS C 5201-1 4.25
40
2℃ with relative humidity 90% to
95%. D.C. rated voltage for 1.5 hours
ON and 30 minutes OFF. Cycle
repeated 1,000 hours
Refer to JIS C 5201-1 4.24
100 G’s for 6milliseconds. 5 pulses
Refer to JIS C 5201-1 4.21
DOCUMENT : SM060000NH
REVISION
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Requirements
R
:
(1.0%+0.0005
)
Without distinct damage in
appearance
R
:
(1.0%+0.0005
)
Without distinct damage in
appearance
Damp Heat with Load
Mechanical Shock
R
:
(0.5%+0.0005
)
Without mechanical damage such
as break
R
:
(0.5%+0.0005
)
Without mechanical damage such
as break
Bending Test
Glass-Epoxy board thickness : 1.6mm
Bending width : 2mm
Between the fulcrums : 90mm
Refer to JIS C 5201-1 4.33
CYNTEC CO., LTD.
乾坤科技股½有限公司
7. Recommended Solder Pad Dimensions
DOCUMENT : SM060000NH
REVISION
PAGE
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: 5 OF 9
D
W
3720
4.2
L
4.0
D
1.4
※0.001ΩCopper
foil thickness of PCB is 105μm.
Unit : mm
Note : We recommend there is no circuit design
between pads to avoid circuit short
W
Cu Trace
Sensing Trace
嵌入式系统
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