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Appendix B: Calibration
Model 2657A High Power System SourceMeter® Instrument Reference Manual
B-8
2657A-901-01 Rev. B/December 2012
Current measurement accuracy
Follow the steps below to verify that Model 2657A current measurement accuracy is within specified
limits. The procedure involves applying accurate currents from the Model 2657A current source and
then verifying that Model 2657A current measurements are within required limits.
1. With the power off, connect the digital multimeter to the Model 2657A terminals as shown in the
figure titled "Connections for current verification" in
(on page B-6).
2. Select the multimeter DC current function.
3. Set the Model 2657A SMU to both source and measure current by pressing the
SRC
and then
the
MEAS
keys. Make sure the source output is turned on.
4. Verify measure current accuracy for each of the currents listed using the values listed in the
following table. For each measurement:
•
Select the correct source range.
•
Set the Model 2657A output current such that the digital multimeter reading is the value indicated in the
source current column of the table below. It may not be possible to set the current source to get exactly
the required reading on the digital multimeter. Use the closest possible setting and modify the reading
limits accordingly.
•
Verify that the Model 2657A current reading is within the limits given in the table below.
Current measurement accuracy limits
Source and measure range*
Source current**
Current reading limits
(1 year, 18 °C to 28 °C)
1 nA***
0.50000 nA
0.498899 nA to 0.501101 nA
0.90000 nA
0.898499 nA to 0.901501 nA
10 nA***
5.0000 nA
4.99000 nA to 5.01000 nA
9.0000 nA
8.98600 nA to 9.01400 nA
100 nA***
50.000 nA
49.8899 nA to 50.1101 nA
90.000 nA
89.8499 nA to 90.1501 nA
1
μ
A 0.50000
μ
A 0.499475
μ
A to 0.500525
μ
A
0.90000
μ
A 0.899375
μ
A to 0.900625
μ
A
10
μ
A 5.0000
μ
A 4.99725
μ
A to 5.00275
μ
A
9.0000
μ
A 8.99625
μ
A to 9.00375
μ
A
100
μ
A 50.000
μ
A 49.9650
μ
A to 50.0350
μ
A
90.000
μ
A 89.9570
μ
A to 90.0430
μ
A
1 mA
0.50000 mA
0.499700 mA to 0.500300 mA
0.90000 mA
0.899620 mA to 0.900380 mA
2 mA
1.0000 mA
0.99930 mA to 1.00070 mA
1.8000 mA
1.79914 mA to 1.80086 mA
20 mA
10.000 mA
9.9930 mA to 10.0070 mA
18.000 mA
17.9914 mA to 18.0086 mA
120 mA
60.000 mA
59.964 mA to 60.036 mA
108.000 mA
107.954 mA to 108.046 mA
* Measure range coupled to source range when simultaneously sourcing and measuring current.
** As measured by precision digital multimeter. Use closest possible value, and modify reading limits
accordingly if necessary. See
Measurement limit calculations
*** Current reading limits assume 1 V burden voltage.
Содержание 2657A
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