FRSM Series FRSM Series (Z1 Foil Technology) Ultra High-Precision FRSM Wrap-Around Chip Resistors, Ultra High-Precision FRSM Wrap-Around Chip Resistors, Z1 Foil Technology Configuration Z1 Foil Technology Configuration with TCR of 0.05 ppm/C and Improved Load-Life Stability of 0.0025% (25 ppm) FEATURES Temperature coefficient of resistance (TCR): 0.05 ppm/C typical (0C to +60C) 0.2 ppm/C typical (55C to +125C, +25C ref.) Resistance tolerance: to 0.01% Power coefficient R due to self heating: 5 ppm at rated power Top View Power rating: to 750 mW at +70C Load life stability: 0.0025% typical at 70C, 2000 h at rated power 0.005% typical at 70C, 10,000 h at rated power INTRODUCTION Resistance range: 5 to 125 k (for higher and lower values, please contact us) The ultra high precision FRSM is based on the new generation Z1 Foil Technology of the Bulk Metal Foil Bulk Metal Foil resistors are not restricted to standard resistor elements by Vishay Foil Resistors (a VPG brand), values specific as required values can be supplied at which makes these resistors virtually insensitive to no extra cost or delivery (e.g., 1K2345 vs. 1K) destabilizing factors (for more information about stresses Thermal stabilization time: <1 s (nominal value achieved and destabilizing factors please refer to Tech Note 102: within 10 ppm of steady state value) www.vishaypg.com/doc 63135). Their element, based on Electrostatic discharge (ESD): at least to 25 kV the Z1 Foil Technology is a solid alloy that displays the desirable bulk properties of its parent material thus, it is Short time overload: 0.005% typical inherently stable (remarkably improved load life stability Rise time: 1 ns, effectively no ringing of 25 ppm), noise-free and withstands ESD to 25 kV or more. The alloy is matched to the substrate and forms a Current noise: <0.010 V /V of applied voltage RMS single entity with balanced temperature characteristics for (<40 dB) an unusually low and predictable TCR over a wide range Voltage coefficient: <0.1 ppm/V (resistance values from 55C to more than 175C. Resistance patterns are above 10 k) photo-etched to permit trimming of resistance values to very tight tolerances. Non-inductive: 0.08 H Our application engineering department is available to Non-hot spot design advise and make recommendations. For non-standard * Terminal finishes available: lead (Pb)-free, tin/lead alloy technical requirements and special applications, please contact us using the e-mail address in the footer below. Matched sets are available on request Screening in accordance with EEE-INST-002 and MIL-PRF-55342 available (see datasheet resistor Table 1Tolerance and TCR vs. models 303261 to 303266) Resistance Value Quick prototype quantities available, please contact us. Typical TCR Resistance Value Tolerance and Spread () (%) (1) (ppm/C) 250 to 125k 0.01% 100 to <250 0.02% 50 to <100 0.05% 0.05 0.5 25 to <50 0.1% * This datasheet provides information about parts that are 10 to <25 0.25% RoHS-compliant and/or parts that are non-RoHS-compliant. For example, parts with lead (Pb)terminations are not RoHS 5 to <10 0.5% compliant. Please see the information/tables in this datasheet (1) From 0C to 60C for details. 4220-EN4220-EN For any questions, contact www.vishayfoilresistors.com Rev 21-Aug-2020Rev 21-Aug-2020 foil vpgsensors.com 1FRSM Series ABOUT THE FRSM SERIES scale conditions. For example, a laboratory instrument that is expected to be permanently installed in an air- Several factors need to be considered when choosing a conditioned laboratory does not need an end-of-life resistor for applications that require long term stability, allowance for excessive heat. There are other reasons for including TCR (ambient temperature), Power TCR (self tolerancing the resistors tighter than the initial calculation: heating), load-life stability for more than 10K hours Measurement equipment accuracy is traditionally ten (instead of the typical 1000 or 2000 hours load-life), times better than the expected accuracy of the devices end-of-life tolerance (which is more important than under test. These tighter tolerance applications require the initial tolerance), thermal EMF (low values, D.C), a high precision resistor. Also, the drift of the resistor thermal stabilization and ESD. Some precision resistor without any stress factor considerations results in a shift technologies such as Precision Thin Film offer designers over time that must be considered. FRSMs have the least tight initial tolerances as low as 0.02 % but have poor amount of time shift. The manufacturers recommended load life stability, high end-of-life tolerance, long thermal recalibration cycle is a factor in the saleability of the stabilization, high drifts during operational life and product and the longer the cycle, the more acceptable the ESD sensitivity. Other resistor technologies, such as product. Bulk Metal Foil resistors contribute significantly Wirewounds, provide low absolute TCR and excellent to the longer calibration cycle. current noise of -40 dB but have high inductance and poor rise time (or thermal lag) for more than a few seconds. Figure 1Power Derating Curve There are essentially only three resistance technologies widely used for precision resistors in military and space - 55 C + 70 C applications: Thin Film, Wirewound and Bulk Metal 100 Foil. Each has its own balance of characteristics and costs that justify its selection in these applications. Thin 75 Films are most cost-efficient within their normal range of 50 characteristics but have the highest TCR, highest noise and have the least stability of the three technologies. 25 Wirewounds have low noise, low TCR and a high level of stability at moderate cost but also have high impedance 0 and slow signal response. Wirewounds can also have a - 75 - 50 - 25 0+ 25 + 50 + 75 + 100 + 125 + 150 + 175 higher power density, but some stability is lost through Ambient Temperature (C) temperature cycling and load-life when made in smaller Lead (Pb)-free terminals configurations. Bulk Metal Foil resistors have the Tin/lead alloy terminals lowest noise, lowest TCR, highest stability and highest speed of any technology but may have a higher cost, depending upon model. With Bulk Metal Foil resistors, savvy designers often save overall by concentrating the circuit stability in the Bulk Metal Foil resistors where Figure 2Trimming to Values exceptional stability allows for use of less-costly active (conceptual illustration) devicesan option not available with other resistor technologies because Bulk Metal Foil foil requires a smaller total error budget through all cumulative resistor Interloop life exposures. Also, Bulk Metal Foil often eliminates extra capacitance Current path reduction circuitry added merely for the purpose of correcting the before trimming in series limitations of other resistor components. FRSM Bulk Metal Foil resistors, based on new generation technology Mutual Current path after trimming and improved production methods starting from inductance reduction February 2011, offer designers the complete set of top Trimming process due to change removes this material performance characteristics to simplify circuitry and lower in current from shorting strip area direction overall system costs by reducing the number of required changing current path and increasing parts while assuring a better end product. The new series resistance of FRSM feature a long-term load-life stability within Foil shown in black, etched spaces in white 0.0025% after 2000 hours and 0.005% after 10000 hours Note under full rated power at +70C, first time in the history of To acquire a precision resistance value, the Bulk Metal Foil all resistor technologies. In addition to their low absolute chip is trimmed by selectively removing built-in shorting bars. TCR of almost zero TCR , the devices offer Power TCR To increase the resistance in known increments, marked (R due to self heating) to 5 ppm at rated power tight areas are cut, producing progressively smaller increases in tolerance from 0.01% and thermal EMF of 0.05 V/C. resistance. This method reduces the effect of hot spots and improves the long-term stability of Bulk Metal Foil resistors. The causes of resistor drift are listed in Table 4 and the allowances shown are for full scale exposure. The designer may choose to use a percentage of full scale stress factor if the equipment will never see the full www.vishayfoilresistors.com For any questions, contact 4220-EN 2 foil vpgsensors.com Rev 21-Aug-2020 Rated Power (%)