SMU ADT220 — Drift Analysis
Drift analysis and trend monitoring for SMU ADT220.
Assessment
TODO: Review drift history and write metrological assessment.
Internal Specification: Analyt MTC — Additel 220 1-year accuracy specifications
Manufacturer Specification: Additel 220 Datasheet — 1-year accuracy specifications
DC 24V Output (V)
| Setpoint (V) | 2019 | 2020 | 2022 | 2024 | 2025 |
|---|---|---|---|---|---|
| As-found Dev/Spec — measured error normalized to internal specification | |||||
| 24 | -0.16 | -0.40 | -0.40 | -0.40 | -0.40 |
| Inter-calibration drift Dev/Spec (Δ) — change since previous calibration, normalized | |||||
| 24 | — | -0.24 | +0.00 | +0.00 | +0.00 |
Figure 1 shows each calibration's as-found deviation normalized to the internal specification. Values at ±1.0 reach the specification limit. The shaded blue envelope covers the full spread across all setpoints; the amber band adds measurement uncertainty (RSS). For the full methodology, see Equipment Monitoring & Drift Analysis.
Figure 2 shows the drift between consecutive calibrations — how much the device changed since it was last calibrated or adjusted. This isolates the device’s instability from corrections applied during calibration.
DC Current Measure (mA)
| Setpoint (mA) | 2019 | 2020 | 2021 | 2022 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| As-found Dev/Spec — measured error normalized to internal specification | ||||||
| -29 | +0.14 | +0.20 | -0.09 | +0.02 | -0.14 | -0.02 |
| 4 | -0.05 | -0.05 | +0.00 | +0.00 | +0.05 | +0.00 |
| 12 | -0.07 | -0.11 | +0.07 | +0.04 | +0.11 | +0.00 |
| 20 | -0.11 | -0.14 | +0.11 | +0.03 | +0.14 | +0.03 |
| 29 | -0.16 | -0.20 | +0.09 | -0.02 | +0.11 | +0.00 |
| Inter-calibration drift Dev/Spec (Δ) — change since previous calibration, normalized | ||||||
| -29 | — | +0.07 | -0.30 | +0.11 | -0.16 | +0.11 |
| 4 | — | +0.00 | +0.05 | +0.00 | +0.05 | -0.05 |
| 12 | — | -0.04 | +0.19 | -0.04 | +0.07 | -0.11 |
| 20 | — | -0.03 | +0.26 | -0.09 | +0.11 | -0.11 |
| 29 | — | -0.05 | +0.30 | -0.11 | +0.14 | -0.11 |
Figure 3 shows each calibration's as-found deviation normalized to the internal specification. Values at ±1.0 reach the specification limit. The shaded blue envelope covers the full spread across all setpoints; the amber band adds measurement uncertainty (RSS). For the full methodology, see Equipment Monitoring & Drift Analysis.
Figure 4 shows the drift between consecutive calibrations — how much the device changed since it was last calibrated or adjusted. This isolates the device’s instability from corrections applied during calibration.
DC Current Source (mA)
| Setpoint (mA) | 2019 | 2020 | 2021 | 2022 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| As-found Dev/Spec — measured error normalized to internal specification | ||||||
| 4 | +0.26 | +0.32 | +0.32 | +0.32 | +0.32 | +0.26 |
| 8 | +0.15 | +0.15 | +0.15 | +0.19 | +0.15 | +0.07 |
| 12 | +0.06 | +0.03 | +0.06 | +0.09 | +0.09 | +0.00 |
| 16 | +0.07 | +0.07 | +0.00 | +0.05 | -0.16 | -0.05 |
| 20 | +0.08 | +0.08 | +0.04 | +0.08 | -0.14 | -0.02 |
| Inter-calibration drift Dev/Spec (Δ) — change since previous calibration, normalized | ||||||
| 4 | — | +0.05 | +0.00 | +0.00 | +0.00 | -0.05 |
| 8 | — | +0.00 | +0.00 | +0.04 | -0.04 | -0.07 |
| 12 | — | -0.03 | +0.03 | +0.03 | +0.00 | -0.09 |
| 16 | — | +0.00 | -0.07 | +0.05 | -0.21 | +0.12 |
| 20 | — | +0.00 | -0.04 | +0.04 | -0.22 | +0.12 |
Figure 5 shows each calibration's as-found deviation normalized to the internal specification. Values at ±1.0 reach the specification limit. The shaded blue envelope covers the full spread across all setpoints; the amber band adds measurement uncertainty (RSS). For the full methodology, see Equipment Monitoring & Drift Analysis.
Figure 6 shows the drift between consecutive calibrations — how much the device changed since it was last calibrated or adjusted. This isolates the device’s instability from corrections applied during calibration.
DC Voltage Measure (V)
| Setpoint (V) | 2019 | 2020 | 2021 | 2022 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| As-found Dev/Spec — measured error normalized to internal specification | ||||||
| -55 | +0.09 | +0.07 | -0.36 | -0.07 | -0.25 | -0.20 |
| -0.29 | -0.16 | -0.16 | -0.45 | -0.41 | -0.48 | -0.32 |
| 0.01 | +0.00 | +0.00 | +0.00 | -0.19 | +0.00 | +0.00 |
| 0.05 | +0.05 | +0.10 | +0.10 | +0.00 | +0.15 | +0.05 |
| 0.1 | +0.12 | +0.12 | +0.20 | +0.12 | +0.24 | +0.16 |
| 0.29 | +0.18 | +0.18 | +0.41 | +0.30 | +0.45 | +0.30 |
| 1 | +0.00 | +0.00 | +0.00 | +0.03 | +0.00 | +0.00 |
| 15 | -0.02 | +0.00 | +0.00 | +0.09 | +0.18 | +0.11 |
| 25 | +0.00 | +0.02 | +0.31 | +0.15 | +0.25 | +0.20 |
| 55 | -0.04 | +0.00 | +0.40 | +0.18 | +0.34 | +0.26 |
| Inter-calibration drift Dev/Spec (Δ) — change since previous calibration, normalized | ||||||
| -55 | — | -0.02 | -0.44 | +0.29 | -0.18 | +0.05 |
| -0.29 | — | +0.00 | -0.30 | +0.05 | -0.07 | +0.16 |
| 0.01 | — | +0.00 | +0.00 | -0.19 | +0.19 | +0.00 |
| 0.05 | — | +0.05 | +0.00 | -0.10 | +0.15 | -0.10 |
| 0.1 | — | +0.00 | +0.08 | -0.08 | +0.12 | -0.08 |
| 0.29 | — | +0.00 | +0.23 | -0.11 | +0.16 | -0.16 |
| 1 | — | +0.00 | +0.00 | +0.03 | -0.03 | +0.00 |
| 15 | — | +0.02 | +0.00 | +0.09 | +0.09 | -0.07 |
| 25 | — | +0.02 | +0.29 | -0.16 | +0.11 | -0.05 |
| 55 | — | +0.04 | +0.40 | -0.22 | +0.16 | -0.08 |
Figure 7 shows each calibration's as-found deviation normalized to the internal specification. Values at ±1.0 reach the specification limit. The shaded blue envelope covers the full spread across all setpoints; the amber band adds measurement uncertainty (RSS). For the full methodology, see Equipment Monitoring & Drift Analysis.
Figure 8 shows the drift between consecutive calibrations — how much the device changed since it was last calibrated or adjusted. This isolates the device’s instability from corrections applied during calibration.
DC Voltage Source (V)
| Setpoint (V) | 2019 | 2020 | 2021 | 2022 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| As-found Dev/Spec — measured error normalized to internal specification | ||||||
| -0.009 | +0.08 | +0.08 | +0.08 | -0.24 | -0.08 | +0.08 |
| 0.01 | +0.16 | +0.08 | +0.16 | -0.08 | +0.08 | +0.08 |
| 0.075 | +0.12 | +0.08 | +0.08 | +0.00 | +0.08 | +0.04 |
| 0.135 | +0.05 | +0.03 | +0.03 | +0.00 | +0.05 | +0.00 |
| 0.19 | +0.04 | +0.00 | +0.00 | +0.00 | +0.04 | -0.02 |
| 2 | +0.10 | +0.10 | +0.10 | +0.20 | +0.20 | +0.10 |
| 4 | +0.29 | +0.29 | +0.36 | +0.36 | +0.36 | +0.29 |
| 6 | +0.22 | +0.28 | +0.28 | +0.33 | +0.33 | +0.28 |
| 8 | +0.32 | +0.36 | +0.41 | +0.45 | +0.45 | +0.36 |
| 10 | +0.27 | +0.31 | +0.38 | +0.42 | +0.42 | +0.31 |
| Inter-calibration drift Dev/Spec (Δ) — change since previous calibration, normalized | ||||||
| -0.009 | — | +0.00 | +0.00 | -0.33 | +0.16 | +0.16 |
| 0.01 | — | -0.08 | +0.08 | -0.24 | +0.16 | +0.00 |
| 0.075 | — | -0.04 | +0.00 | -0.08 | +0.08 | -0.04 |
| 0.135 | — | -0.03 | +0.00 | -0.03 | +0.05 | -0.05 |
| 0.19 | — | -0.04 | +0.00 | +0.00 | +0.04 | -0.06 |
| 2 | — | +0.00 | +0.00 | +0.10 | +0.00 | -0.10 |
| 4 | — | +0.00 | +0.07 | +0.00 | +0.00 | -0.07 |
| 6 | — | +0.06 | +0.00 | +0.06 | +0.00 | -0.06 |
| 8 | — | +0.05 | +0.05 | +0.05 | +0.00 | -0.09 |
| 10 | — | +0.04 | +0.08 | +0.04 | +0.00 | -0.12 |
Figure 9 shows each calibration's as-found deviation normalized to the internal specification. Values at ±1.0 reach the specification limit. The shaded blue envelope covers the full spread across all setpoints; the amber band adds measurement uncertainty (RSS). For the full methodology, see Equipment Monitoring & Drift Analysis.
Figure 10 shows the drift between consecutive calibrations — how much the device changed since it was last calibrated or adjusted. This isolates the device’s instability from corrections applied during calibration.
