Approval sheet WF12W, WF08W, WF06W, WF04W 0.5%, 0.25%, 0.1%, 0.05% TC10 High Precision Thin Film chip resistors Size 1206, 0805, 0603, 0402 *Contents in this sheet are subject to change without prior notice. Page 1 of 7 ASC_WFxxW_V06 Nov.2011 Approval sheet FEATURE 1. SMD metal film resistor 2. High reliability and stability of 0.25% and below per customer request 3. High performance of TCR: 10 ppm/K and below per customer request 4. Low current noise 5. RoHS compliant and lead free APPLICATION * Medical equipment * Measuring instrument * Communication device * Computer * Printer 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 layer that is applied to the top surface of the substrate. The composition of the resistive layer 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 environmental soldering issue, the outer layer of these end terminations is a Lead-free solder . Fig 1. Construction of Chip-R WFxxW Page 2 of 7 ASC_WFxxW_V06 Nov.2011 Approval sheet QUICK REFERENCE DATA Item General Specification Series No. WF12W WF08W WF06W WF04W Size code 1206 ( 3216 ) 0805 ( 2012 ) 0603 ( 1608 ) 0402 ( 1005 ) 0.5%, 0.25%, 0.1%, 0.05% * Resistance Tolerance Resistance Range 25 ~ 300K ( E24 +E192 ) 25 ~ 200K ( E24 +E192 ) 25 ~ 100K ( E24 +E192 ) 25 ~ 20K ( E24 +E192 ) 10 ppm/C TCR (ppm/C) Max. dissipation at Tamb=70C 1/8W 1/8W 1/10W 1/16W Max. Operation Voltage (DC or RMS) 150V 100V 50V 25V Max. Overload Voltage (DC or RMS) 300V 200V 100V 50V Operation temperature - 55~ +155'C 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. 3. Tolerance 0.05% is upon requested DIMENSIONS:(unit:mm) Type WF12W WF08W WF06W WF04W L 3.05 0.15 2.00 0.10 1.55 0.10 1.00 0.10 W 1.55 0.15 1.25 0.10 0.80 0.10 0.50 0.05 A 0.40 0.20 0.25 0.20 0.25 0.15 0.15 0.10 B 0.40 0.20 0.40 0.20 0.30 0.15 0.25 0.10 t 0.55 0.15 0.50 0.15 0.45 0.15 0.30 0.05 Protective coat t End termination B Resistive layer A Ceramic Substrate W T 1001 L Page 3 of 7 ASC_WFxxW_V06 Nov.2011 Approval sheet MARKING 3-digits marking for 0603 size WFxxW has same marking rule as WRxx 1%. 4-digits marking for 1206, 0805 size For E24+E96, each resistor is marked with a four digits code on the protective coating to designate the nominal resistance value. For values below 976 the R is used as a digit. For values of 100 or greater, the first 3 digits are significant, the fourth digit indicates the number of multiple to follow. Example RESISTANCE 100 6800 47000 4-digits marking 1000 6801 4702 No marking code for 0402 size FUNCTIONAL DESCRIPTION Product characterization Standard values of nominal resistance are taken from the E192 & E24 series for resistors with a tolerance of 0.5%, 0.25%, 0.1%. The values of the E24/E192 series are in accordance with "IEC publication 60063". Derating The power that the resistor can dissipate depends on the operating temperature; see Fig.2 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 ASC_WFxxW_V06 Nov.2011 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 within lead-free solder bath. 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 Fig 3. CATALOGUE NUMBERS The resistors have a catalogue number starting with . WF06 W xxxx B T L Size code Type code Resistance code Tolerance Packaging code Termination code WF12: 1206 W: TCR 10ppm E192+E24: A : 0.05% T : Reeled L = lead free WF08: 0805 R is first code followed by B : 0.10% WF06: 0603 3 significant digits. C : 0.25% WF04: 0402 100 =1000 D : 0.50% 37.4K =3742 1. Reeled tape packaging: 8mm width paper taping. 5,000pcs/reel for WF12W, WF08W, WF06W; 10,000pcs/reel for WF04W. Page 5 of 7 ASC_WFxxW_V06 Nov.2011 Approval sheet TEST AND REQUIREMENTS(JIS C 5201-1 : 1998) TEST REQUIREMENT PROCEDURE Resistor DC resistance DC resistance values measured Clause 4.5 <10@0.1V, Within the specified tolerance <100@0.3V, <1K@1.0V, <10K@3V, <100K@10V,<1M@25V, <10M@30V Temperature Coefficient of Resistance(T.C. R) Clause 4.8 Natural resistance change per change in degree Refer to centigrade. " QUICK REFERENCE DATA " R2 - R1 x 106 R1 (t2 - t1 ) (ppm/C) R1 : Resistance at reference temperature R2 : Resistance at test temperature t1 : 20C+5C-1C t2 : 125C+5C-1C Short time overload (S.T.O.L) Clause 4.13 Resistance to soldering heat(R.S.H) IEC 60068-258:2004 Solderability IEC 60068-258:2004 Temperature cycling Clause 4.19 Load life (endurance) Permanent resistance change after a 5second R/R max. (0.1%+0.05) application of a voltage 2.5 times RCWV or the maximum overload voltage specified in the above list, whichever is less. Un-mounted chips completely immersed for no visible damage 101second in a SAC solder bath at 260 R/R max. (0.1%+0.05) 5C Un-mounted chips completely immersed for good tinning (>95% covered) 20.5 second in a SAC solder bath at 2355 no visible damage 30 minutes at -55C3C, 2~3 minutes at no visible damage 20C+5C-1C, 30 minutes at +155 C3C, R/R max. (0.25%+0.05) 2~3 minutes at 20C+5C-1C, total 5 continuous cycles 702C, 1000 hours, loaded with RCWV or R/R max. (0.25%+0.05) Vmax,1.5 hours on and 0.5 hours off Clause 4.25 Load life in Humidity Clause 4.24 Bending strength Clause 4.33 Adhesion Clause 4.32 Page 6 of 7 1000 hours, at rated continuous working voltage R/R max. (0.25%+0.05) in humidity chamber controller at 40C2C and 90~95% relative humidity, 1.5hours on and 0.5 hours off Resistors mounted on a 90mm glass epoxy resin R/R max. (0.1%+0.05) PCB(FR4); bending : 3 mm, once for 10 seconds. Pressurizing force: 5N, Test time: 101sec. No remarkable damage or removal of the terminations. ASC_WFxxW_V06 Nov.2011 Approval sheet PACKAGING Paper Tape specifications (unit :mm) P0 F D Series No. A B W D E WF12 3.600.20 2.000.20 8.000.30 3.500.20 1.750.10 WF08 2.400.20 1.650.20 8.000.30 3.500.20 1.750.10 WF06 1.900.20 1.100.20 8.000.30 3.500.20 1.750.10 WF04 1.200.10 0.70.10 8.000.20 3.500.05 1.750.10 Series No. F P0 D T WF12 4.000.10 4.000.10 1.50 +-00..10 Max. 1.0 WF08 4.000.10 4.000.10 1.50 +-00..10 Max. 1.0 WF06 4.000.10 4.000.10 1.50 +-00..10 0.650.05 WF04 2.000.10 4.000.10 1.50 +-00..10 0.400.05 Reel dimensions B C A D Symbol A B C D (unit : mm) 178.02.0 60.01.0 13.00.2 9.00.5 Taping quantity - Chip resistors 5,000 pcs per reel ( WF12W, WF08W, WF06W ) - Chip resistors 10,000 pcs per reel ( WF04W ) Page 7 of 7 ASC_WFxxW_V06 Nov.2011