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Essay On Si Traceability Chain

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The SI traceability chain is shown in Fig. 6. The DUTs are calibrated with a current source and voltmeter. The current source is calibrated using the NIST TS CVC [3, 5]. The TS CVC’s feedback resistors are calibrated (in situ) by comparison to NIST workings standards calibrated in terms of the quantum Hall effect. The voltmeter DC voltage is calibrated by comparison to a NIST 10 V Josephson Voltage Standard (JVS). Both the resistance and DC voltage calibrations are carried out by the NIST Quantum Measurement Division (QED). Fig. 6. SI traceability for the NIST CVC calibration system. 4.1 Transfer Standard CVC Feedback Resistors Calibration Calibrating the feedback resistors are key to the traceability. As mentioned above, the TS CVC …show more content…

There are also small differences in the uncertainties depending on which current source is used for the measurements. Uncertainties propagated using the Keithley 263 and 6430 current sources are given below. 5.1 Transfer Standard CVC Typical calibration results and uncertainty for the feedback resistors of the TS CVC and the Val CVC are summarized in Table 1. The resistor serial numbers are prefaced by 1010 for the TS CVC and 1000 for the Val CVC. Table 1. Feedback resistance calibration values for the TS CVC (SN: 1010) and Val CVC (SN: 1000). Resistor Serial No. Nominal Value (Ω) Calibration Temp. (°C) Calibration Voltage Correction (x10-6) Exp. Uncert. (k=2) (x10-6) Change / year (x10-6) 1000-10K 1 x 104 22.99 10 V, 1 mA 17.4 0.3 2.27 1010-10K 1 x 104 22.98 10 V, 1 mA 43.8 0.3 2.13 1000-100K 1 x 105 23.00 10 57.0 0.8 1.19 1010-100K 1 x 105 23.00 10 91.2 0.8 1.45 1000-1M 1 x 106 23.00 10 46.2 0.8 3.31 1010-1M 1 x 106 23.00 10 55.4 0.8 3.74 1000-10M 1 x 107 22.99 10 147 6 7.61 1010-10M 1 x 107 22.99 10 100 6 3.81 1000-100M 1 x 108 22.98 10 57 6 7.79 1010-100M 1 x 108 22.98 10 113 6 6.23 1000-1G 1 x 109 23.00 10 841 18 2.08 1010-1G 1 x 109 23.00 10 -282 18 1.90 1000-10G 1 x 1010 23.01 10 857 50 -6.92 1010-10G 1 x 1010 23.01 10 -18 50 -5.19 5.2 Current Source Calibration The uncertainty of the current source calibration has two terms. The first term is an absolute uncertainty that

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