Approval sheet WR18X(W), WR20X(W), WR25X(W) 1%, 5% Thick Film Power Chip Resistors Size 1218,2010,2512 *Contents in this sheet are subject to change without prior notice. Page 1 of 7 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet 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 products APPLICATION * Power supply * PDA * Digital meter * Computer * Automotives * Battery charger * DC-DC power converter 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 Tin (lead free) alloy. Fig 1. Construction of 2512, 2010 Chip-R Fig 2. Construction of a 1218 Chip-R Page 2 of 7 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet QUICK REFERENCE DATA Item General Specification Series No. WR18X(W) WR20X(W) WR25X(W) Size code 1218(3248) 2010 ( 5025 ), 2512(6432) 5% (E24); 1% (E24+E96) Resistance Tolerance Resistance Range 1 ~ 10M, Jumper (0) 100 ppm/C 100 ppm/C 100 ppm/C 200 ppm/C 200 ppm/C 200 ppm/C 1W 0.75 W 1W Max. Operation Voltage (DC or RMS) 200V 200V 250V Max. Overload Voltage (DC or RMS) 400V 400V 500V TCR (ppm/C) : 10< Rn 10M 1 Rn 10 Max. dissipation at Tamb=70C Operation temperature -55 ~ +155'C Storage temperature 5 ~ 40'C Test conditions for jumper ( 0 ohm ) Type WR18X(W) WR20X(W) WR25X(W) 1W 3/4 W 1W Resistance Max. 50mR Max. 50mR Max. 50mR Rated Current 4.5 A 3.8 A 4.5 A Peak Current 11 A 9A 11 A Operating Temperature -55C ~ 155C -55C ~ 155C -55C ~ 155C Power Rating At 70C 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 RCWV = Rated Power x Resistance Value or Max. RCWV listed above, whichever is lower. MECHANICAL DATA (unit : mm) TYPE WR18 WR20 WR25 L 3.050.15 5.000.20 6.400.20 W 4.600.20 2.500.20 3.200.20 T 0.550.10 0.550.10 0.600.10 Tt 0.450.25 0.650.25 0.650.25 Tb 0.500.25 0.600.25 0.900.25 Page 3 of 7 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet MARKING Each resistor is marked with value. Example: 1R00 1001 0000 a four-digit code on the protective coating to designate the nominal resistance = = = 1 1000 0 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 Figure 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. Page 4 of 7 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet SOLDERING CONDITION The robust construction of chip resistors allows them to be completely immersed in a solder bath of 260C 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 235C during 2 seconds. The test condition for no leaching is 260C for 30 seconds. Typical examples of soldering processes that provide reliable joints without any damage are given in below. CATALOGUE NUMBERS 3-5 sec The resistors have a catalogue number starting with . WR20 X 472_ J T L Size code Type code Resistance code Tolerance Packaging code Termination code WR25 : 2512 X: J : 5% T : 7" Reel taping WR20 : 2010 5%: 1-10M 5% E24 : 2 significant digits followed by no. of zeros and a blank F : 1% (T:1218 10" Reel) L = Sn base (lead free) WR18: 1218 1%: 10-1M 4.7 =4R7_ P : Jumper Q : 10" Reel taping W: 10 =100_ 1% : <10 or >1M Page 5 of 7 G : 13" Reel taping 1% E24+E96: 3 significant digits followed by no. of zeros 102 =1020 37.4K =3742 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet TEST AND REQUIREMENTS(JIS C 5201-1 : 1998) 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: 15C to 35C. 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. TEST PROCEDURE DC resistance DC resistance values measured at the test voltages specified below : Clause 4.5 <10@0.1V,<100@0.3V, <1K@1.0V, <10K@3V, <100K@10V, <1M@25V, <10M@30V Temperature Coefficient of Resistance(T.C.R) Natural resistance change per change in degree centigrade. Clause 4.8 R2 - R1 x 106 R1 (t2 - t1 ) (ppm/C) t1 : 20C+5C-1C REQUIREMENT Within the specified tolerance Refer to "QUICK REFERENCE DATA" R1 : Resistance at reference temperature R2 : Resistance at test temperature Short time overload (S.T.O.L) Clause Clause 4.13 Resistance to soldering heat(R.S.H) Clause 4.18 Solderability Clause 4.17 Permanent resistance change after a 5second application of a voltage R/R max. (2%+0.1) 2.5 times RCWV or the maximum overload voltage specified in the above list, whichever is less. Un-mounted chips completely immersed for 101second in a SAC no visible damage solder bath at 2605C R/R max. (1%+0.05) Un-mounted chips completely immersed for 20.5 second in a SAC good tinning (>95% solder bath at 2355 covered) no visible damage Temperature cycling 30 minutes at -55C3C, 2~3 minutes at 20C+5C-1C, 30 minutes at +155C3C, 2~3 minutes at 20C+5C-1C, total 5 continuous cycles Load life (endurance) 1000 +48/-0 hours, loaded with RCWV or Vmax in chamber controller 702C, 1.5 hours on and 0.5 hours off Clause 4.25 Load life in Humidity 1000 +48/-0 hours, loaded with RCWV or Vmax in humidity chamber controller at 40C2C and 90~95% relative humidity, 1.5hours on and Clause 4.24 0.5 hours off Clause 4.19 no visible damage R/R max. (1%+0.05) R/R max. (3%+0.1) R/R max. (3%+0.1) Clause 4.33 Resistors mounted on a 90mm glass epoxy resin PCB(FR4); R/R max. (1%+0.05) bending : 2 mm, once for 10 seconds Adhesion Pressurizing force: 5N, Test time: 101sec. Clause 4.32 Insulation Resistance Apply the maximum overload voltage (DC) for 1minute R10G Clause 4.6 Dielectric Withstand Apply the maximum overload voltage (AC) for 1 minute No breakdown or flashover Bending strength No remarkable damage or removal of the terminations Voltage Clause 4.7 Page 6 of 7 WR18-20-25X(W)_V17 DEC - 2016 Approval sheet PACKAGING Plastic Tape specifications (unit :mm) Type A B WR18 4.900.20 3.550.30 WR20 5.500.20 2.800.20 WR25 6.900.20 3.600.20 Type P1 WR18 8.000.10 WR20 W F E 12.000.30 5.500.10 1.750.10 P0 D T 4.000.10 1.50 +-00..10 1.300.20 4.000.10 MAX1.2 WR25 Reel dimensions (unit : mm) Symbol A B C D 7" Reel 178.02.0 60.01.0 13.00.2 12.4.01.00 10" Reel 254.02.0 100.01.0 13.00.2 14.00.20 13" Reel 330.02.0 100.01.0 13.00.2 14.00.20 Taping quantity WR20, WR25 by plastic tape taping 4,000 pcs per 7" reel; 8,000pcs per 10" reel; 16,000pcs per 13" reel ! WR18 by plastic tape taping 3,000 pcs per 10" reel Page 7 of 7 WR18-20-25X(W)_V17 DEC - 2016