Z Series (Z Foil)Z Series (Z Foil) Ultra High PrUltra High Precision Z Foil Though-Hole Resistorecision Z Foil Though-Hole Resistor with TCR of 0.2ppm/C, Tolerance of 0.005% (50ppm), Load Life Stability of 0.005% FEATURES Temperature coefficient of resistance (TCR): 0.2 ppm/C typical (55C to +125C, +25C ref.) (see table 1) Rated power: to 1W at +125C (see table 2) Resistance tolerance: to 0.005% (50 ppm) Load life stability: 0.005% at 70C, 2000 h or 0.015% at 70C, 10000 h (see table 4) The stability of a resistor depends primarily on its history Resistance range: 5 to 600 k of exposures to temperature. Stability is affected by: Bulk Metal Foil resistors are not restricted to standard 1. Reversible changes in the ambient temperature values specific as required values can be supplied and heat from adjacent components (defined by the at no extra cost or delivery (e.g. 1K2345 vs. 1K) Temperature Coefficient of Resistance, or TCR) Total accumulated change in resistance value over life 2. Short-term steady-state self-heating (defined by or Total Error Budget <0.1% (or tighter with PMO)** Power TCR or PCR) Electrostatic Discharge (ESD): at least to 25 kV 3. Irreversible destabilizing shock of suddenly-applied Non-inductive, non-capacitive design power Rise time: 1 ns effectively no ringing 4. Long-term exposure to applied power (load-life Current noise: 0.010 V /V of applied voltage RMS stability) (<40 dB) In very high-precision resistors, these effects must be Thermal EMF: 0.05 V/C typical taken into account to achieve high stability with changes Voltage coefficient: <3 ppm/V in load (Joule Effect) and ambient temperature. Low inductance: <0.08 H typical Vishay Foil Resistors Z Foil technology provides an order Thermal stabilization time <1 s (to reach within 10 ppm of magnitude reduction in the Bulk Metal Foil elements of steady state value) sensitivity to temperature changes both external and internal. This technology provides TCR of 0.2 ppm/C Pattern design minimizing hot spots typical (military range: 55C to +125C, +25C ref), and a Terminal finish: lead (Pb)-free or tin/lead alloy PCR of 5 ppm at rated power. Matched sets are available per request In order to take full advantage of this TCR improvement, (TCR tracking: to 0.5 ppm/C) it is necessary to take into account the differences in Military established reliability R level resistor available the resistors response to each of the above-mentioned (see resistor model RNC90Z) effects. The Z series has been developed to successfully Screen/test flow as modified from S-311-P813 deal with these factors. proposed by NASA available (see datasheet for resistor model 303143) * This datasheet pr ovides information about parts that are RoHS-compliant and/or parts that are non-RoHS-compliant. Prototype quantities available please contact For example, parts with lead (Pb) terminations are not foil vpgsensors.com RoHS compliant. Please see the information/tables in this datasheet for details. INTRODUCTION ** See PMO page 5 The Bulk Metal Foil resistor is based on a special thermo-metalic stress concept wherein a proprietary bulk metal cold rolled foil is cemented to a ceramic substrate. TABLE 1 TYPICAL TCR AND MAX. SPREAD It is then photoetched into a resistive pattern. Then it is laser adjusted to any desired value and tolerance. (55C to +125C, +25C ref.) Because the metals used are not drawn, wound or STANDARD TYPICAL TCR AND VALUE mistreated in any way during manufacturing process, TOLERANCE MAX. SPREAD (ppm/C) the Bulk Metal Foil resistor maintains all its design, 100 to 600 k 0.005% 0.2 0.6 physical and electrical characteristics while winding 80 to <100 0.005% 0.2 0.8 of wire or sputtering does not. Z Foil resistors achieve 50 to <80 0.01% 0.2 1.0 maximum stability and near-zero TCR. These performance 25 to <50 0.01% 0.2 1.3 characteristics are built-in for every unit, and do not 10 to <25 0.02% 0.2 1.6 rely on screening or other artificial means for uniform 5 to <10 0.05% 0.2 2.3 performance. Document No.: 63187Document No.: 63187 For any questions, contact www.vishayfoilresistors.com Revision: 01-Nov-2016Revision: 01-Nov-2016 foil vpgsensors.com 1Z Series (Z Foil)Z Series (Z Foil) FIGURE 1 TYPICAL RESISTANCE/ FIGURE 2 POWER DERATING CURVE TEMPERATURE CURVE (for more details, see table 1) - 55 C + 70 C 100 TCR Values for Different Temperature Ranges Rated Power +500 +400 75 +300 +200 +100 R 50 R 0 (ppm) 100 0.05 ppm/C 200 0.1 ppm/C0.1 ppm/C 25 300 0.14 ppm/C 400 0.16 ppm/C 0.2 ppm/C 500 55 25+0+25 60 +75+100+125 0 - 75 - 50 - 25 0+ 25 + 50 + 75 + 100 + 125 + 150 + 175 + 200 Ambient Temperature (C) Ambient Temperature (C) Note The TCR values for <100 are influenced by the termination composition and result in deviation from this curve FIGURE 3 TRIMMING TO VALUES (conceptual illustration) Interloop Capacitance Current Path Reduction Before Trimming Note in Series To acquire a precision resistance value, the Bulk Metal Foil chip is trimmed by selectively removing built-in shorting bars. Current Path After Trimming Mutual Inductance To increase the resistance in known increments, Reduction due marked areas are cut, producing progressively Trimming Process to Change in smaller increases in resistance. This method Removes this Material Current Direction reduces the effect of hot spots and improves from Shorting Strip Area the long-term stability of Bulk Metal Foil resistors. Changing Current Path and Increasing Resistance Foil shown in black, etched spaces in white FIGURE 4 -THROUGH-HOLE STYLE (29 YEARS) 40 20 0 -20 -40 -60 -80 -100 -120 05 10 15 20 25 30 Time (Years) www.vishayfoilresistors.com For any questions, contact Document No.: 63187 2 foil vpgsensors.com Revision: 01-Nov-2016 R/R (ppm) Rated Power (%) at + 70