Approval sheet
Page 1 of 7 ASC_MR18-20-25X_V03 June.2011
MR18X, MR20X, MR25X
±
±±
±1%, ±
±±
±5%
Power chip resistors
Size 1218, 2010, 2512
( Automotive & Anti-sulfuration )
*Contents in this sheet are subject to change without prior notice.
Approval sheet
Page 2 of 7 ASC_MR18-20-25X_V03 June.2011
FEATURE
1. High power rating and compact size
2. High reliability and stability
3. Reduced size of final equipment
4. RoHS compliant and Lead free product
APPLICATION
• Power supply
• Industry
• Motor control
• M/B Computer
• Automotives
• Servo
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. Construction of 2512, 2010 Chip-R
Fig 2. Construction of 1218 Chip-R
Approval sheet
Page 3 of 7 ASC_MR18-20-25X_V03 June.2011
QUICK REFERENCE DATA
Item General Specification
Series No. MR18 MR20 MR25
Size code 1218(3248) 2010 ( 5025 ), 2512(6432)
Resistance Tolerance ±5% (E24); ±1% (E24+E96)
Resistance Range 1Ω ~ 10MΩ, Jumper (0Ω)
± 200 ppm/°C ± 200 ppm/°C ± 200 ppm/°C
± 100 ppm/°C ± 100 ppm/°C ± 100 ppm/°C
TCR (ppm/°C) < 10Ω
10Ω ~ 1MΩ
> 1MΩ ± 200 ppm/°C ± 200 ppm/°C ± 200 ppm/°C
Max. dissipation at T
amb
=70°C 1W 0.5 W 1W
Max. Operation Voltage (DC or RMS) 200V 200V 250V
Max. Overload Voltage (DC or RMS) 400V 400V 500V
Climatic category (IEC 60068) 55/155/56
Test conditions for jumper ( 0 ohm )
Type
MR18X MR20X MR25X
Power Rating At 70C
1 W 1/2 W 1 W
Resistance
Max. 50mR Max. 50mR Max. 50mR
Rated Current
4.5 A 3.2 A 4.5 A
Peak Current
11 A 8 A 11 A
Operating Temperature
-55C ~ 155℃
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.
MECHANICAL DATA (unit : mm)
TYPE MR18 MR20 MR25
L 3.05±0.15
5.00±0.20
6.40±0.20
W 4.60±0.20
2.50±0.20
3.20±0.20
T 0.55±0.10
0.55±0.10
0.60±0.10
Tt 0.45±0.25
0.65±0.25
0.65±0.25
Tb 0.50±0.25
0.60±0.25
0.90±0.25
Approval sheet
Page 4 of 7 ASC_MR18-20-25X_V03 June.2011
MARKING
Each resistor is marked with a four-digit code on the protective coating to designate the nominal resistance
value
±
5%,
±
1% tolerance !
Size ±
±±
±5% ±
±±
±1%
2512, 2010, 1218
4-digits marking 4-digits marking
FUNCTIONAL DESCRIPTION
Product characterization
Standard values of nominal resistance are taken from the E96 & E24 series for resistors with a tolerance of ±5%
& ±1%. The values of the E24/E96 series are in accordance with “IEC publication 60063”.
Derating curve
The power that the resistor can dissipate depends on the operating temperature; see Fig.3
Fig 3
Maximum dissipation in percentage of rated power as a
function of the ambient temperature
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 4.
Fig 4. Infrared soldering profile for Chip Resistors
Approval sheet
Page 5 of 7 ASC_MR18-20-25X_V03 June.2011
CATALOGUE NUMBERS
The resistors have a catalogue number starting with .
MR25 X 472_ J T L
Size code
MR25 : 2512
MR20 : 2010
MR18 : 1218
Type code
X :
±5%: 1Ω-10MΩ
±1%: 10Ω-1MΩ
W :
±1%: < 10Ω; >1MΩ
Resistance code
±5%: E24: 2 significant digits
followed by no. of zeros
100Ω = 101_
10KΩ = 103
±11%: 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
Q : 10” Reeled taping
G : 13” Reeled taping
B : Bulk
Termination
code
L = Sn base
(lead free)
* Anti-Sulfuration test conditions: H2S 3ppm, 40’C, RH 90%, 1000hrs, criteria: +/-1% !
* 100% CCD visual inspection to guarantee visual quality !
TEST AND REQUIREMENTS
Essentially all tests are carried out according to the schedule of IEC publication 115-8, category
LCT/UCT/56(rated temperature range : Lower Category Temperature, Upper Category Temperature; damp
heat, long term, 56 days). The testing also meets the requirements specified by EIA, EIAJ and JIS.
The tests are carried out in accordance with IEC publication 68, "Recommended basic climatic and mechanical
robustness testing procedure for electronic components" and under standard atmospheric conditions according
to IEC 60068-1, subclause 5.3. Unless otherwise specified, the following value supplied :
Temperature: 15°C to 35°C.
Relative humidity: 45% to 75%.
Air pressure: 86kPa to 106 kPa (860 mbar to 1060 mbar).
All soldering tests are performed with midly activated flux.
REQUIREMENT
TEST PROCEDURE / TEST METHOD Resistor 0Ω
ΩΩ
Ω
Electrical
Characteristics
JISC5201-1: 1998
Clause 4.8
-
DC resistance values measurement
-
Temperature Coefficient of Resistance (T.C.R)
Natural resistance change per change in degree centigrade.
( )
6
121
12 10×
−
−
ttR RR
(ppm/°C) t
1
: 20°C+5°C-1°C
R
1
: Resistance at reference temperature
R
2
: Resistance at test temperature
Within the specified tolerance
Refer to “QUICK REFERENCE DATA”
Resistance to
soldering heat
(R.S.H)
MIL-STD-202
method 210
Un-mounted chips completely immersed for 10±1second in a SAC
solder bath at 270℃±5ºC ∆R/R max. ±(0.5%+0.05Ω)
No visible damage
Approval sheet
Page 6 of 7 ASC_MR18-20-25X_V03 June.2011
REQUIREMENT
TEST PROCEDURE / TEST METHOD Resistor 0Ω
ΩΩ
Ω
Solderability
J-STD-002
a) Bake the sample for 155 ℃dwell time 4hrs/ solder dipping
235℃/ 5sec.
b) Steam the sample dwell time 1 hour/ solder dipping
260℃/ 7sec.
95% coverage min., good tinning and no
visible damage
Temperature cycling
JESD22
Method JA-104
1000 cycles, -55℃ ~ +155℃, dwell time 5~10min ∆R/R max. ±(0.5%+0.05Ω)
No visible damage <50mΩ
Moisture Resistance
MIL-STD-202
method 106
65±2°C, 80~100% RH, 10 cycles, 24 hours/ cycle ∆R/R max. ±(0.5%+0.05Ω)
No visible damage <50mΩ
Bias Humidity
MIL-STD-202
method 103
1000+48/-0 hours; 85°C, 85% RH, 10% of operation power ∆R/R max. ±(1.0%+0.05Ω)
No visible damage <50mΩ
Operational Life
MIL-STD-202
method 108
1000+48/-0 hours; 35% of operation power, 125±2°C ∆R/R max. ±(1%+0.05Ω)
No visible damage <50mΩ
High Temperature
Exposure
MIL-STD-202
Method 108
1000+48/-0 hours; without load in a temperature chamber
controlled 155±3°C ∆R/R max. ±(1.0%+0.05Ω)
No visible damage
<50mΩ
Mechanical Shock
MIL-STD-202
method 213
1/2 Sine Pulse / 1500g Peak / Velocity 15.4ft/sec Within the specified tolerance
No visible damage <50mΩ
Board Flex
AEC-Q200-005 Resistors mounted on a 90mm glass epoxy resin PCB(FR4),
bending once 2mm for 10sec
∆R/R max. ±(1.0%+0.05Ω).
No visible damage <50mΩ
Terminal strength
AEC-Q200-006 Pressurizing force: 1.8Kg, Test time: 60±1sec.
No remarkable damage or removal of
the terminations
Vibration
MIL-STD-202
method 204
Test 5g’s for 20min., 12 cycles each of 3 orientations ∆R/R max. ±(1.0%+0.05Ω)
No visible damage <50mΩ
Thermal shock
MIL-STD-202
method 107
Test –55 to 155℃/ dwell time 15min/ Max transfer time 20sec
300cycles ∆R/R max. ±(0.5%+0.05Ω)
No visible damage <50mΩ
ESD
AEC-Q200-002
Test contact 3.0KV ∆R/R max. ±(1.0%+0.05Ω).
No visible damage <50mΩ
Approval sheet
Page 7 of 7 ASC_MR18-20-25X_V03 June.2011
PACKAGING
Plastic Tape specifications (unit :mm)
Type A B W F E
WR18 4.90±0.20 3.55±0.30
WR20 5.50±0.20 2.80±0.20
WR25 6.90±0.20 3.60±0.20
12.00±0.30 5.50±0.10 1.75±0.10
Type P1 P0 ΦD T
WR18 8.00±0.10 1.30±0.20
WR20
WR25 4.00±0.10 4.00±0.10
1.0 0.0
50.1
+
−
Φ
MAX1.2
Reel dimensions
Symbol A B C D
(unit : mm) Φ178.0±2.0 Φ60.0±1.0 13.0±0.2 14.0±0.2
Taping quantity
WR20, WR25 by plastic tape taping 4,000 pcs per reel.
WR18 by plastic tape taping 3,000 pcs per reel
