VHZ Hermetic (Z-Foil)VHZ Hermetic (Z-Foil) New Generation of Secondary Standards Hermetically Sealed New Generation of Secondary Standards Hermetically Sealed Construction Ultra High Precision Z-Foil Technology Resistors Construction Ultra High Precision Z-Foil Technology Resistors with TCR of 0.2 ppm/C, Tolerance of 0.005% and Load Life Stability of 0.005% for 10 000h (Metrology, Laboratory, Instrumentation, Industrial) FEATURES Temperature coefficient of resistance (TCR): 0.2 ppm/C typical (55C to +125C, +25C ref.). For ultra high performances (instrumentation and metrology) please contact us Load life stability to 0.005% (50 ppm) at 70C, 10000h at 0.15 W (see table 3) Load life stability, can be considerably improved through in-house stabilization (PMO) Resistance range: 5 to 121 k (higher or lower values of resistance available) Table 1 TCR vs. Resistance Value Power coefficient R due to self heating: TYP. TCR AND 5 ppm at rated power with the Z-Foil technology STANDARD MAX. SPREAD MODEL VALUE TOLERANCE 55C TO +125C Tolerance: to 0.005% (50 ppm) (2) (+25C ref.) Electrostatic discharge (ESD) up to 25000V 100 to 100 k 0.005% 0.20.6 ppm/C Power Rating: 0.6 W at +70C 0.3 W at +125C 80 to <100 0.005% 0.20.8 ppm/C Thermal EMF: 0.1 V/C maximum, 0.05 V/C typical 1 V/C VH102Z 50 to <80 0.01% 0.21.0 ppm/C 7 Hermeticity: 10 atmospheric cc/s maximum 25 to <50 0.01% 0.21.3 ppm/C Non-inductive, non-capacitive design 10 to <25 0.02% 0.21.6 ppm/C Non hot spot design 80 to 121 k 0.005% 0.21.8 ppm/C Rise time: 1 ns effectively no ringing Current noise: 0.010 V /V of applied voltage 30.1 to 80 0.005% 0.22.3 ppm/C RMS VHZ555 (1) (<40dB) (PMO) 20 to <30.1 0.01% 0.22.3 ppm/C Voltage coefficient: <0.1 ppm/V 4.99 to <20 0.05% 0.22.8 ppm/C Thermal stabilization time <1 s (nominal value achieved within 10 ppm of steady state value) Non-inductive: <0.08 H Figure 1 Power Derating Curve Terminal finish available: lead (Pb)-free or tin/lead alloy 55C +70C Double Rated Power +200 Prototype quantities available in just 5 working days or sooner. For more information, please contact: +175 foil vpgsensors.com +150 For better performances (values, TCR, tolerance, stability), please contact us +125 Rated Power +100 +75 +50 +25 0 75250 25 0 25 50 75 100 125 150 175 00 Ambient Temperature (C) Notes * Pb containing terminations are not RoHS compliant, exemptions may apply (1) VHZ555 units are manufactured on the same production line facilities and are subjected to all the same process and lot control requirements imposed on RNC90Z version, as well as all of the special screening, environmental conditioning and documentation stipulations outlined in MIL-PRF 55182/9 (2) TCR of 0.2 ppm/C Max. is achievable per special request 4129-EN4129-EN For any questions, contact www.foilresistors.com Rev 15-Sep-2021Rev 15-Sep-2021 foil vpgsensors.com 1 Percent of Rated Power at +125 CVHZ Hermetic (Z-Foil)VHZ Hermetic (Z-Foil) (1) Table 2 Specifications AMBIENT POWER RATING MAXIMUM WORKING RESISTANCE VALUE AVERAGE WEIGHT VOLTAGE at +70C at +125C 100K 0.6 W 0.3 W 300 V 1.4g >100K 0.4 W 0.2 W Note (1) Resistance figures are obtained by measuring the leads at point 0.5 in (12.7 mm) 0.13 in (3.2 mm) away from the root. ABOUT VHZ HERMETIC The VHZ series of resistors is the hermetically sealed characteristics tolerance, long-term shelf life and load version of the Z201. Hermetic sealing eliminates the stability, temperature coefficient, noise, capacitance ingress of both oxygen, which degrades resistors over and inductance are optimum, approaching in total long periods, and moisture which degrades resistors performance the theoretical ideal, more quickly. These parts are made with glass to metal a straight wire. seal enclosures employing Kovar eyelets which allow the VHZ was developed by VFR as a new resistor concept, copper leads to pass through the enclosure to minimize through the use of a proprietary Bulk Metal Foil and the thermal EMF from the lead junctions. new ultra-fine photo-etching techniques created by the Rubber fill between the metal housing and resistance company, so that the conductor can be considered a flat element acts both as a mechanical damper and thermal wire. Because the metals used are not drawn, wound or transfer path. VH102Z is the hermetically-sealed mistreated in any way during the manufacturing process, counterpart of the Z201 high-performance molded VHZ resistors maintain all of their design, physical and resistors. VHZ555 is the hermetically-sealed version of the electrical characteristics. Z555, MIL style RNC90Z (ER). The temperature coefficient of the resistor is carefully The VHZ Series is designed and manufactured to controlled through compensation techniques to eliminate eliminate the inter-parameter compromise inherent the effect of different coefficients of expansions for all in all other types of precision resistors. All important materials used in the resistor. Figure 2 Trimming to Values Figure 3 Typical Resistance/Temperature Curve (Z-Foil) Interloop capacitance TCR Chord Slopes for Different Temperature Ranges Current path reduction before trimming +500 in series +400 +300 Mutual Current path after trimming +200 inductance reduction +100 Trimming process R due to change removes this material R 0 in current from shorting strip area (ppm) direction 100 0.05 ppm/C changing current path and increasing 200 0.1 ppm/C0.1 ppm/C resistance 300 0.14 ppm/C Foil shown in black, etched spaces in white 400 0.16 ppm/C 0.2 ppm/C Note 500 To acquire a precision resistance value, the Bulk Metal Foil 55 25 0 +25 +60+75 +100 +125 chip is trimmed by selectively removing built-in shorting bars. Ambient Temperature (C) To increase the resistance in known increments, marked areas are cut, producing progressively smaller increases in resistance. This method reduces the effect of hot spots and improves the long-term stability of Bulk Metal Foil resistors. www.foilresistors.com For any questions, contact 4129-EN 2 foil vpgsensors.com Rev 15-Sep-2021