CYNTEC CO., LTD.
DOCUMENT : SR550000N
REVISION : A1
PAGE : 1 OF 8
2550 3/4W Low Resistance Chip Resistor
1. Scope
This specification applies to 2.5mm x 5.0mm size 3/4W, fixed metal film chip resistors rectangular type
for use in electronic equipment.
2. Type Designation
RL2550 L
-
-
N
(1) (2)
(3)
(4) (5)
Where (1)
Series
No.
(2) L = L Type
(3) Resistance value :
For example - -
R003 = 3m
R100 = 100m
(4)
Resistance
tolerance
F =
1%
G =
2%
J =
5%
(5) N = Sn plating (Lead free , RoHS compliant)
3. Outline Designation and Marking
3-1 Outline Designation
(1) Substrate
Alumina 96%
(2) Resistor
Ni-Cu alloy
(3) Terminals
Sn (on Cu )
(4) Protection coat
Heat resistive epoxy resin
(5) Marking
Epoxy resin
Dimensions (mm)
Code Letter
RL2550
L
5.0
0.20
W
2.5
0.20
a
1.00
0.15
t
(3m
) 0.80 0.15
(3m
) 0.95 0.15
Figure 1. Construction and Dimensions
W
t
L
(Bottom View)
a
a
(1)
(2)
(3)
(4)
(5)
R003
CYNTEC CO., LTD.
DOCUMENT : SR550000N
REVISION : A1
PAGE : 2 OF 8
3-2 Marking
Resistance value is marked on the top surface. Ex.) 47m
R047
100m
R100
4. Ratings
4-1 Specification
Power Ratings*
3/4W
Resistance Value** 1 ~ 50m
Temperature Coefficient of Resistance
(
10m) 100ppm/
(>10m
) 50ppm/
Resistance Tolerance
1% , 2% , 5%
Insulation Resistance
Over 100M
Maximum Working Voltage (V)
( P*R)
1/2
Note * :
Power ratings is based on continuous full load operation at rated ambient temperature of 70.
For resistors operated at ambient temperature in excess of 70, the maximum load shall be
derated in accordance with the following curve.
Figure 2.Power Temperature Derating Cure
4-2 Maximum over current
[ ]
ms
A
R
I
10
/
/
50
=
Where
I : maximum current 40A
R : Nominal resistance value (
)
Interval 60 seconds minimum
If maximum current so obtained exceed than 40A , use 40A as maximum current.
4-3 Operation and Storage Temperature Range
-55 to +125
0
70
100
125
-55
AMBIENT TEMPERATURE( )
RAT
ED LO
AD(%
)
CYNTEC CO., LTD.
DOCUMENT : SR550000N
REVISION : A1
PAGE : 3 OF 8
5. Schematic Diagram. Measurement Point
6. Life test
6-1 Electrical
6-1-1 Short Time Overload
Resistance Change :
( 0.5% + 0.0005 )
Without significant damage by flashover ( spark, arching ), burning or
breakdown etc.
Test voltage : 2.5 times the rated voltage.
Duration : 5 seconds
6-1-2 Insulation Resistance
(1) Between Electrode and Protection Film
100M
or over
(2) Between Electrode and Substrate
R0.5
Substrate
Protection Film
Pressure Rod
Measurement Point A
(Metal)
Test Sample
Spring
Insulation Prate
Metal Block
Measurement Point B
1,000M
or over
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 5202 5.6 Mounting condition G.
Measurement Point
Schtemtic Diagram
I
V
V Current terminal
Voltage terminal
I
R047
I
V
CYNTEC CO., LTD.
DOCUMENT : SR550000N
REVISION : A1
PAGE : 4 OF 8
6-2 Mechanical
6-2-1 Solderability
A new uniform coating of solder shall cover minimum of 95% of the surface
being immersed.
Temperature of solder : 245
5
Immersion duration : 3
0.5 seconds
6-2-2 Resistance to Soldering Heat
Resistance change :
( 0.5% + 0.0005 )
Electrical characteristics shall be satisfied.
Without distinct deformation in appearance
Dipped into solder for 10
1 seconds at 270 5
6-2-3 Substrate bending
Resistance change :
( 0.5% + 0.0005 )
Without mechanical damage such as breaks.
Electrical characteristics shall be satisfied.
Glass-Epoxy bard t = 1.6mm
Bending value : 2mm
Between the fulcrums : 90mm
CYNTEC CO., LTD.
DOCUMENT : SR550000N
REVISION : A1
PAGE : 5 OF 8
6-3 Endurance
6-3-1 Rapid change of temperature
Resistance change :
( 0.5% + 0.0005 )
Without distinct damage.
Perform 5 cycles as follows :
-55 for 30minutes room temperature for 3 minutes
+125 for 30minutes room temperature for 3 minutes
6-3-2 Endurance at 70
Resistance change :
( 0.5% + 0.0005 )
Without distinct damage.
Rated voltage for 1.5 hours followed by a pause 0.5 hour at a temperature of 70
3.
Cycle shall be repeated for 1,000 hours.
6-3-3 Dump heat with load
Resistance change :
( 0.5% + 0.0005 )
The marking shall be legible.
60
2 with relative humidity of 90% to 95%.
D.C. rated voltage for 1.5 hours ON 30 minutes OFF.
Cycle shall be repeated for 1,000 hours.
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