333 3 WSHM2818 www.vishay.com Vishay Dale Power Metal Strip Resistors, High Power (7 W), Low Value (Down to 0.001 ), Surface Mount FEATURES Improved thermal management incorporated into design All welded construction of the Power Metal Strip resistors are ideal for all types of current sensing, voltage division, and pulse applications Proprietary processing technique produces extremely low resistance values Sulfur resistance by construction that is unaffected by high sulfur environments Very low inductance (< 5 nH) Solid metal nickel-chrome or manganese- copper alloy resistive element with low TCR LINKS TO ADDITIONAL RESOURCES (< 20 ppm/C) Low thermal EMF (< 3 V/C) (1) AEC-Q200 qualified 3D Models Design Tools Videos PATENT(S): www.vishay.com/patents Material categorization: for definitions of compliance please see www.vishay.com/doc 99912 Notes Follow link to Overview of Automotive Grade Products for more details: www.vishay.com/doc 49924 (1) Flame retardance test may not be applicable to some resistor technologies STANDARD ELECTRICAL SPECIFICATIONS RESISTANCE VALUE RANGE POWER RATING WEIGHT GLOBAL MODEL SIZE P (typical) 70 C W g/1000 pieces TOL. 0.5 % TOL 1.0 % (1) WSHM2818 2818 7 0.010 to 0.1 0.001 to 0.1 167.8 WSHM2818 2818 6 0.101 to 0.2 0.101 to 0.2 167.8 Note (1) The WSHM2818 is rated at 7 W with maximum surface temperature of 180 C GLOBAL PART NUMBER INFORMATION Global Part Numbering: WSHM2818R1000FEA (visit www.vishay.net Vishay Dale parts numbering manual for all options) W S H M 2 8 1 8 R 1 0 0 0 F E A RESISTANCE (1) GLOBAL MODEL TOLERANCE CODE PACKAGING CODE SPECIAL VALUE WSHM2818 L = m* D = 0.5 % EA = lead (Pb)-free, tape / reel (dash number) R = decimal F = 1.0 % EK = lead (Pb)-free, bulk (up to 2 digits) 4L000 = 0.004 from 1 to 99 as R0100 = 0.01 applicable * Use L for resistance values < 0.01 Notes SMD Power Metal Strip Marking (www.vishay.com/doc 30327) (1) Packaging code: EB (lead (Pb)-free) and TB (tin / lead) are non-standard packaging codes designating 1000 piece reels. These non-standard packaging codes are identical to our standard EA (lead (Pb)-free) and TA (tin / lead), except that they have a package quantity of 1000 pieces PATENT(S): www.vishay.com/patents This Vishay product is protected by one or more United States and international patents. Revision: 29-Mar-2021 Document Number: 30188 1 For technical questions, contact: ww2bresistors vishay.com THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000 DDD D WSHM2818 www.vishay.com Vishay Dale TECHNICAL SPECIFICATIONS PARAMETER UNIT RESISTOR CHARACTERISTICS 200 for 1 m to 5.99 m (1) Component temperature coefficient (including terminal) ppm/C 75 for 6 m to 200 m (2) Element TCR ppm/C < 20 Inductance nH < 5 Operating temperature range C -65 to +170 (3) 1/2 Maximum working voltage V(P x R) Notes (1) Component TCR - total TCR that includes the TCR effects of the resistor element and the copper terminal (2) Element TCR - only applies to the alloy used for the resistor element refer to item 1 in the construction illustration on the following page (3) Maximum working voltage - the WSHM is not voltage sensitive, but is limited by power / energy dissipation and is also not ESD sensitive DIMENSIONS in inches (millimeters) L H a T b l W a Notes 3D models available: www.vishay.com/doc 30324 Surface mount solder profile recommendations: www.vishay.com/doc 31052 RESISTANCE DIMENSIONS SOLDER PAD DIMENSIONS MODEL RANGE LW H T a b l 0.280 0.010 0.180 0.010 0.059 0.010 0.125 0.010 0.138 0.200 0.024 WSHM2818 0.001 to 0.2 (7.1 0.25) (4.6 0.25) (1.50 0.25) (3.18 0.25) (3.5) (5.1) (0.61) TYPICAL SENSING LAYOUT SENSING WITH VIA LAYOUT (best performance) a f a e a a c b b l l d c ab c l ab de f l 0.138 0.210 0.020 0.024 0.143 0.210 0.026 0.105 0.020 0.024 (3.51) (5.33) (0.51) (0.61) (3.63) (5.33) (0.66) (2.67) (0.50) (0.61) Note Sensing locations are based on the construction of the part terminals are wrapped from the outside to underneath. These options place the sensing location nearest the temperature stable resistance element, which minimizes contact resistance and optimizes TCR Revision: 29-Mar-2021 Document Number: 30188 2 For technical questions, contact: ww2bresistors vishay.com THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE. THE PRODUCTS DESCRIBED HEREIN AND THIS DOCUMENT ARE SUBJECT TO SPECIFIC DISCLAIMERS, SET FORTH AT www.vishay.com/doc 91000