WF12G, WF08G, WF06G, WF04G 1%, 5%, 11M~100M High ohmic chip resistors Size 1206, 0805, 0603, 0402 Page 1 of 7 WFxxG_V11 Jul.2010 00-S-R03-G FEATURE 1. Small size and light weight 2. High reliability and stability 3. Reduced size of final equipment 4. High precision 5. Higher component and equipment reliability 6. RoHS compliant and lead free products. APPLICATION * Power supply * PDA * Digital meter * Computer * Palmtop computers 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. Consctruction of Chip-R Page 2 of 7 WFxxG_V11 Jul.2010 00-S-R03-G QUICK REFERENCE DATA Item General Specification Series No. WF12G WF08G WF06G WF04G Size code 1206 ( 3216 ) 0805 ( 2125 ) 0603 ( 1608 ) 0402 ( 1005 ) Resistance Tolerance Resistance Range TCR (ppm/C) 1%, 5% 5% 10M < R 100M 10M < R 30M ( E24 series) 200 ppm/C 300 ppm/C Max. dissipation at Tamb=70C 1/4 W 1/8 W 1/10 W 1/16W Max. Operation Voltage (DC or RMS) 200V 150V 50V 50V Climatic category (IEC 60068) 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 RCWV = Rated Power x Resistance Value or Max. RCWV listed above, whichever is lower. DIMENSIONS(unit : mm) series WF12G WF08G WF06G WF04G L 3.10 0.15 2.00 0.10 1.60 0.10 1.00 0.05 W 1.60 0.15 1.25 0.10 0.80 0.10 0.50 0.05 Tt 0.50 0.25 0.40 0.20 0.30 0.10 0.20 0.10 Tb 0.50 0.25 0.40 0.20 0.30 0.15 0.25 0.10 T 0.55 0.10 0.50 0.15 0.45 0.15 0.35 0.05 MARKING 3-digits marking Each resistor is marked with a three digits code on the protective coating to designate the nominal resistance value. For values up to 9.1 the R is used as a decimal point. For values of 10.0 or greater the first 2 digits apply to the resistance value and third indicate the number of zeros to follow. Example 306 = 30 M 186 = 18 M Page 3 of 7 WFxxG_V11 Jul.2010 00-S-R03-G FUNCTIONAL DESCRIPTION Product characterization Standard values of nominal resistance are taken from the E96 & E24 series for resistors with a tolerance of 5%. The values of the E24/E96 series are in accordance with "IEC publication 60063". Derating The power that the resistor can dissipate depends on the operating temperature; see Fig.2 Figure 2. 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 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 Fig 3. Fig 3. Infrared soldering profile for Chip Resistors Page 4 of 7 WFxxG_V11 Jul.2010 00-S-R03-G CATALOGUE NUMBERS The resistors have a catalogue number starting with : WF06 G 226_ J T L Size code Type code Resistance code Tolerance Packaging code Termination code WF12 : 1206 G : High ohmic >10M J : 5% T : 7" Reeled taping WF08 : 0805 1206 size=0.25W 5% E24: 2 significant digits followed by no. of zeros and a blank F : 1% B : Bulk L = Sn base (lead free) WF06 : 0603 0805 size=0.125W WF04 : 0402 0603 size=0.10W 11M =116_ 22M =226_ 30M =306_ ("_" means a blank) 1%, E24+E96: 3 significant digits followed by no. of zeros 100 =1000 37.4K =3742 1. Reeled tape packaging : 8mm width paper taping 5000pcs per 7" reel for 1206, 0805, 0603 ( 10,000pcs for 0402 ) 2. Bulk packaging : 5000pcs per polybag TEST AND REQUIREMENTS(JIS C 5201-1 : 1998) TEST Temperature Coefficient of Resistance (T.C.R) Clause 4.8 PROCEDURE Natural resistance change per change in degree centigrade. R2 - R1 x 106 R1 (t2 - t1 ) REQUIREMENT Refer to quick reference data for T.C.R specification. (ppm/C) R1 : Resistance at reference temperature R2 : Resistance at test temperature t1 : 20C+5C-1C t2 : Test temperature. Short time overload (S.T.O.L) Permanent resistance change after a 5 second application of a No visible damage. voltage 2.5xUR or max. Overload voltage, whichever is less. R/R max. J: (2%+0.1) Clause 4.13 Solderability Clause 4.17 Resistance to soldering heat(R.S.H) F: (1%+0.05) Un-mounted chips completely immersed for 20.5 second in a SAC good tinning (>95% covered) solder bath at 2355. no visible damage Un-mounted chips completely immersed for 101second in a SAC No visible damage. solder bath at 2605C R/R max. J: (1%+0.1) F: (0.5%+0.05) Clause 4.18 Page 5 of 7 WFxxG_V11 Jul.2010 00-S-R03-G TEST PROCEDURE REQUIREMENT Temperature cycling 1. 30 minutes at -55C3C, No visible damage. Clause 4.19 2. 2~3 minutes at 20C+5C-1C, R/R max. J (1%+0.1) 3. 30 minutes at +1553C, 4. 2~3 minutes at 20C+5C-1C, F (0.5%+0.05) Total 5 continuous cycles. Load life (endurance) 1000 +48/-0 hours, loaded with RCWV or Vmax in chamber No visible damage. controller 702C, 1.5 hours on and 0.5 hours off R/R max. J (3%+0.1) Clause 4.25 F (1%+0.05) Load life in Humidity 1000 +48/-0 hours, loaded with RCWV or Vmax in humidity chamber No visible damage. controller at 40C2C and 90~95% relative humidity, 1.5hours on Clause 4.24 R/R max. J (3%+0.1) and 0.5 hours off F (1%+0.05) Bending strength Clause 4.33 Adhesion Resistors mounted on a 90mm glass epoxy resin PCB(FR4); R/R max. (1%+0.10) bending : 3 mm, once for 10 seconds Pressurizing force: 5N, Test time: 101sec. Clause 4.32 Insulation Resistance Apply the maximum overload voltage (DC) for 1minute No remarkable damage or removal of the terminations. R10G Clause 4.6 Dielectric Withstand Apply the maximum overload voltage (AC) for 1 minute No breakdown or flashover Voltage Clause 4.7 Page 6 of 7 WFxxG_V11 Jul.2010 00-S-R03-G PACKAGING Paper Tape specifications (unit :mm) Series No. A B W F E WF12G 3.600.20 2.000.20 8.000.30 3.500.2 1.750.10 WF08G 2.400.20 1.650.20 8.000.30 3.500.2 1.750.10 WF06G 1.900.20 1.100.20 8.000.30 3.500.2 1.750.10 P1 P0 D T WF12G 4.000.10 4.000.10 4.000.10 4.000.10 1.50 +-00..10 Max. 1.0 WF08G WF06G 4.000.10 4.000.10 Series No. 0.650.1 Reel dimensions 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/reel for 1206, 0805, 0603 ( 10,000 pcs/reel for 0402 ) Page 7 of 7 WFxxG_V11 Jul.2010 00-S-R03-G