E4981B Capacitance Meter

Definitions and Specifications

This document provides specifications and supplemental information for the Keysight Technologies, Inc. E4981B capacitance meter. All specifications apply to the conditions of a 0 °C to 45 °C temperature range, unless otherwise stated, and 30 minutes after the instrument has been turned on.

Sample Calculation of Measurement Accuracy

This section describes an example for calculating the measurement accuracy of each measurement parameter, assuming the following measurement conditions.

Sample

• Measurement signal frequency: 1 kHz

• Measurement signal level: 0.5 V

• Measurement range: 10 nF

• Measurement time mode: N = 1

• Ambient temperature: 28 °C

When measurement parameter is Cp-D (or Cs-D)

The following is an example for calculating the accuracy of Cp (or Cs) and D, assuming that measured result of Cp (or Cs) is 8.00000 nF and measured result of D is 0.01000.

From Table 16, the equation to calculate the accuracy of Cp (or Cs) is 0.055 + 0.030 × K and the equation to calculate the accuracy of D is 0.00035 + 0.00030 × K

The measurement signal level is 0.5, the measurement range is 10 nF, and the measured result of Cp (or Cs) is 8.00000 nF. Therefore, K = (1/0.5) × (10/8.00000) = 2.5

Substitute this result into the equation. As a result, the accuracy of Cp (or Cs) is 0.055 + 0.030 × 2.5 = 0.13% and the accuracy of D is 0.00035 + 0.00030 × 2.5 = 0.0011

Therefore, the true Cp (or Cs) value exists within 8.00000 ± (8.00000 × 0.13/100) = 8.00000 ± 0.0104 nF that is, 7.9896 nF to 8.0104 nF and the true D value exists within 0.01000 ± 0.0011 that is, 0.0089 to 0.0111

When measurement parameter is Cp-Q (or Cs-Q)

The following is an example for calculating the accuracy of Cp (or Cs) and Q, assuming that measured result of Cp (or Cs) is 8.00000 nF and measured result of Q is 20.0.

The accuracy of Cp (or Cs) is the same as that in the example of Cp-D. From Table 17, the equation to calculate the accuracy of D is 0.00035 + 0.00030 × K

Substitute K = 2.5 (same as Cp-D) into this equation.

The accuracy of D is 0.00035 + 0.00030 × 2.5 = 0.0011

Then, substitute the obtained D accuracy into equation in Table 12.

The accuracy of Q is ±(20.0)2 × 0.0011/(1 ∓ 20.0 × 0.0011) = ±0.44/(1 ∓ 0.022) that is, –0.43 to 0.45

Therefore, the true Q value exists within the range of 19.57 to 20.45

When measurement parameter is Cp-G

The following is an example for calculating the accuracy of Cp and G, assuming that measured result of Cp is 8.00000 nF and measured result of G is 1.00000 μS. The accuracy of Cp is the same as that in the example of Cp-D.

From Table 12, the equation to calculate the accuracy of G is (Ce/100) × 2 × π × f × Cx

Substitute Ce = 0.13% (same as Cp-D) and Cx = 8.00000 nF of the measured Cp result into this equation. The accuracy of G is (0.13/100) × 2 × π × 1 × 103 × 8 × 10–9 = 65.35 nS (0.065 μS)

Therefore, the true G value exists within 1.00000 ±0.065 μS that is, 0.935 μS to 1.065 μS