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Page 1 of 7 ASC_WW25-20-18X_V11 AUG - 2016 WW25X , WW20X, WW18X Thick Film Low Ohm Power Chip Resistors Size 2512, 2010, 1218 RoHS Compliant and Halogen free *Contents in this sheet are subject to change without prior notice.

Page 2 of 7 ASC_WW25-20-18X_V11 AUG - 2016 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 a Lead-tin alloy. Fig 1. Construction of 2512, 2010 Chip-R Fig 2. Construction of a 1218 Chip-R

Page 3 of 7 ASC_WW25-20-18X_V11 AUG - 2016 QUICK REFERENCE DATA Item General Specification Series No. WW25X WW20X WW18X Size code 2512 ( 6432 ) 2010(5025) 1218(3248) Resistance Tolerance ±5% (E24) ±1% ±5% (E24) ±1% ±5% (E24) ±1% TCR (ppm/ °C) 0.01Ω ≤ Rn < 0.05 Ω 0.05 Ω ≤ Rn < 0.10 Ω 0.10 Ω ≤ Rn < 0.50 Ω 0.50 Ω ≤ Rn < 1 Ω ≤ 2100 ppm/ °C ≤ 1000 ppm/ °C ≤ 500 ppm/ °C ≤ 400 ppm/ °C ≤ 1500 ppm/ °C ≤ 1000 ppm/ °C ≤ 500 ppm/ °C ≤ 300 ppm/ °C Max. dissipation at T amb =70 °C 1 W 0.5 W 1 W Climatic category (IEC 60068) 55/155/56 55/155/56 55/155/56 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 Value Resistance Power Rated RCWV ×= or Max. RCWV listed above, whichever is lower. MECHANICAL DATA(unit : mm) Symbol \\ size 2512 2010 1218

Page 4 of 7 ASC_WW25-20-18X_V11 AUG - 2016 MARKING Each resistor is marked with a four-digit code on the protective coating to designate the nominal resistance value. Example: R010 = 0.01 Ω R510 = 0.51 Ω 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. Max. 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 5 of 7 ASC_WW25-20-18X_V11 AUG - 2016 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 CATALOGUE NUMBERS The resistors have a catalogue number starting with . WW25 X R020 J T L Size code WW25 : 2512 WW20 : 2010 WW18 : 1218 Type code X : Normal Resistance code E96 +E24: R is first digit followed by 3 significant digits. 0.020 Ω = R020 0.510 Ω = R510 0.025 Ω = R025 Tolerance J : ±5% F : ±1% D : ±0.5% Packaging code T : 7” Reeled Q : 10” Reeled Termination code L = Sn base (lead free)

Page 6 of 7 ASC_WW25-20-18X_V11 AUG - 2016 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 C ategory Temperature, U pper C ategory 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. TEST PROCEDURE REQUIREMENT Temperature Coefficient of Resistance(T.C.R) Clause 4.8 Natural resistance change per change in degree centigrade. ( ) 12 1 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 Refer to “QUICK REFERENCE DATA” Short time overload (S.T.O.L) Clause 4.13 Permanent resistance change after a 5second application of a voltage 2.5 times RCWV or the maximum overload voltage specified in the above list, whichever is less. ΔR/R max. ±(2%+0.005 Ω ) Resistance to soldering heat(R.S.H) Clause 4.18 Un-mounted chips completely immersed for 10 ±1 second in a SAC solder bath at 260 ℃±5ºC no visible damage Δ R/R max. ±(1% +0.005 Ω ) Solderability Clause 4.17 Un-mounted chips completely immersed for 2±0.5 second in a SAC solder bath at 235℃±5 ℃ good tinning (>95% covered) no visible damage Temperature cycling Clause 4.19 30 minutes at -55 °C ±3°C, 2~3 minutes at 20° C+5° C-1° C, 30 minutes at +155 °C ±3°C, 2~3 minutes at 20° C+5° C-1° C, total 5 continuous cycles no visible damage ΔR/R max. ±(1% +0.005 Ω ) Load life (endurance) Clause 4.25 1000 +48/-0 hours, loaded with RCWV or Vmax in chamber controller 70 ±2ºC, 1.5 hours on and 0.5 hours off ΔR/R max. ±(3% +0.005 Ω ) Load life in Humidity Clause 4.24 1000 +48/-0 hours, loaded with RCWV or Vmax in humidity chamber controller at 40 °C ±2°C and 90~95% relative humidity, 1.5hours on and 0.5 hours off ΔR/R max. ±(3% +0.005 Ω ) Bending strength Clause 4.33 Resistors mounted on a 90mm glass epoxy resin PCB(FR4); bending : 2 mm, once for 10 seconds ΔR/R max. ±(1% +0.005 Ω ) Adhesion Clause 4.32 Pressurizing force: 5N, Test time: 10 ±1sec. No remarkable damage or removal of the terminations Insulation Resistance Clause 4.6 Apply the maximum overload voltage (DC) for 1minute R ≧10G Ω Dielectric Withstand Voltage Clause 4.7 Apply the maximum overload voltage (AC) for 1 minute No breakdown or flashover

Page 7 of 7 ASC_WW25-20-18X_V11 AUG - 2016 PACKAGING Plastic Tape specifications (unit :mm) Symbol A B W F E 2512 6.90 ±0.20 3.60 ±0.20 2010 5.50±0.20 2.80±0.20 1218 4.90 ±0.20 3.55 ±0.30 Symbol P1 P0 Φ D T 2512 Max. 1.2 2010 Max. 1.2 1218 8.00 ±0.10 4.00 ±0.10 1 . 0 0 . 050 . 1+ Φ 1.30±0.20 Reel dimensions (unit : mm) A B C D Taping quantity ‧ WW20, WW25 by plastic tape taping 4,000 pcs per 7” reel / 8,000pcs per 10” reel! ‧ WW18 by plastic tape taping 3,000 pcs per 10” reel