CSM SeriesCSM Series Bulk Metal Technology High Precision, Current Sensing, Bulk Metal Technology High Precision, Current Sensing, Power Surface Mount, Metal Strip Resistor Power Surface Mount, Metal Strip Resistor with Resistance Value from 1 m, Rated Power up to 3 W and TCR to 015 ppm/C Maximum FEATURES Temperature coefficient of resistance: 15 ppm/C max. (55C to +125C, +25C ref.) 10 ppm/C max. (55C to +125C, +25C ref.) is available on request (see table 1) Power rating: 1 W to 3 W Resistance tolerance: 0.1% Resistance range: 1 m to 200 m INTRODUCTION Bulk Metal Foil resistors are not restricted to standard values, specific as required values can be supplied at No minimum order quantity and any value at any no extra cost or delivery (e.g., 2.3456 m vs. 2 m) tolerance available within resistance range. Load life stability to 0.2% (70C, 2000 h The Vishay Foil Resistors (VFR) application engineering at rated power) department is available to advise and make Short time overload: 0.1% typical recommendations. Thermal EMF: 3 V/C (DC offset error, significant For non-standard technical requirements and special for low values) applications, please contact: foil vpgsensors.com. Maximum current: up to 54 A Proprietary processing techniques produce low TCR, BC tight tolerance and improve stability R Low inductance <5 nH I I Solderable terminations Excellent frequency response to 50 MHz A D Screening in accordance with EEE-INST002 V available (per MIL-PRF-55342 and MIL-PRF-49465 ~ Zin = see 303144 and 303145 datasheets) Terminal finishes available: lead (Pb)-free, tin/lead alloy Four terminal (Kelvin) design: allows for precise and Quick prototype quantities available, accurate measurements. please contact: foil vpgsensors.com For better performance please contact: Figure 1 Power Derating Curve application engineering +70C 100 80 60 40 20 0 65 50 25 0255075 100 125 150 170 Ambient Temperature (C) Notes * This datasheet provides information about parts that are RoHS-compliant and/or parts that are non-RoHS-compliant. For example, parts with lead (Pb) terminations are not RoHS compliant. Please see the information/tables in this datasheet for details. 4138-EN4138-EN For any questions, contact www.vishayfoilresistors.com Rev 11-Jan-2021Rev 11-Jan-2021 foil vpgsensors.com 1 Rated Power (%)CSM SeriesCSM Series Table 1 Specifications PARAMETER CSM2512 CSM3637 Resistance Range 1 m to 200 m 3 W (1 m to 10 m) (1) Power Rating at 70C 1 W 2 W (>10 m to 200 m) (2) Maximum Current 31 A 54 A 0.5% (1 m to <3 m) 0.5% (1 m to <2 m) Tolerance 0.1% (3 m to 200 m) 0.1% (2 m to 200 m) 50 ppm/C (1 m to <3 m) 25 ppm/C (1 m to <3 m) (3) (3) Temperature Coefficient Max. 15 ppm/C (3 m to 200 m) 15 ppm/C (3 m to 200 m) (55C to +125C, +25C Ref.) 10 ppm/C (3 m to 10 m) 10 ppm/C (1 m to 10 m) (4) (4) is available on request is available on request Operating Temperature Range 65C to +170C 1/2 Maximum Working Voltage (P R) Weight (Maximum) 0.09 g 0.29 g Notes (1) For values above 0.1 derate linearly to 80% rated power at 0.5 (2) Maximum current for a given resistance value is calculated using I = P/R (3) Loose TCR is available on request: 35ppm/C (3m to 200m) (4) Please contact application engineering: foil vpgsensors.com ABOUT CSM (Low Ohm Value 1 m to 200 m) New high-precision Bulk Metal surface-mount Power The device features a low thermal electromotive force Metal Strip resistor of 1 m to 200 m that features (EMF) that is critical in many precision applications. an improved load-life stability of 0.2% at +70C for The CSMs all-welded construction is composed of a Bulk 2000 h at rated power, an absolute TCR of 15 ppm/C Metal resistive element with welded copper terminations, maximum from 55C to +125C, +25C ref., and a plated for soldering. The terminations make true ohmic tolerance of 0.1%. contact with the resistive layer along the entire side of Typical current sensing resistors offer a load-life stability the resistive element, thereby minimizing temperature of 1% through a 2000 h workload. The improved variations. Also, the resistor element is designed to resistance stability of the CSM Series makes it ideal for uniformly dissipate power without creating hot spots, and tightened-stability voltage division and precision current the welded terminations material is compatible with the sensing applications in switching linear power supplies, element material. power amplifiers, measurement instrumentation, bridge These design factors result in a very low thermal- networks, and medical and test equipment. In addition, EMF (3 V/C) resistor, because in addition to the low the CSM Series complies with EEE-INST-002 thermal EMF compatibility of the metals, the uniformity (MIL-PRF 55342 and MIL-PRF 49465) for military and and thermal efficiency of the design minimizes the space applications. temperature differential across the resistor, thereby Traditional Passive current sensors and shunts generate assuring low thermal EMF generation at the leads. This heat under power, which changes their resistance, further reduces the battery effect exhibited by most and thus their voltage output. The CSMs low absolute current-sensing or voltage-reference resistors. Thus, TCR reduces errors due to temperature gradients, the parasitic voltage generated at the junction of two thus reducing a major source of uncertainty in current dissimilar metals, which is especially important in low- measurement. The CSM can withstand unconventional value current-sensing resistors, is minimized, while the environmental conditions, including the extremely high pure current-to-voltage conversion is protected from such temperatures and radiation-rich environments of down- interference in DC applications. hole oil exploration and well logging, or the deep-sea The stability problems associated with analog circuits underwater repeaters in cross-ocean communications. are very pervasive, but knowledgeable selection of The stability of the CSM can be further enhanced by a few high-quality resistors, networks, or trimming post-manufacturing operations (PMO), such as potentiometers temperature cycling, short-time overload, and in critical locations can greatly improve circuit accelerated load life which are uniquely applicable to performance, long-term application-related performance, Bulk Metal Foil resistors. as well as the designers peace-of-mind. Notes * This datasheet provides information about parts that are ROHS-compliant and/or parts that are non-ROHS-compliant. For example , parts with lead (Pb) terminations. Please see the information /tables in this datasheet for details. www.vishayfoilresistors.com For any questions, contact 4138-EN 2 foil vpgsensors.com Rev 11-Jan-2021