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Section 3: Functions and features
Model 2657A High Power System SourceMeter® Instrument Reference Manual
3-66
2657A-901-01 Rev. B/December 2012
Command interface
Turning on High-C mode has the following effects on the SMU settings:
•
smua.measure.autorangei
is set to
smua.AUTORANGE_FOLLOW_LIMIT
and cannot be
changed.
•
Current ranges below 1
μ
A are not accessible.
•
If
smua.source.limiti
is less than 1
μ
A, it is raised to 1
μ
A.
•
If
smua.source.rangei
is less than 1
μ
A, it is raised to 1
μ
A.
•
If
smua.source.lowrangei
is less than 1
μ
A, it is raised to 1
μ
A.
•
If
smua.measure.lowrangei
is less than 1
μ
A, it is raised to 1
μ
A.
Measuring current
The following inputs are required to test leakage using the factory leakage script, as shown in the
script example below.
•
SMU:
Sets the Model 2657A source-measure unit to use
•
levelv:
Sets the output voltage level
•
limiti:
Sets the current limit for discharging or charging the capacitor
•
sourcedelay:
Solve the following equation to determine the amount of time before taking a current
reading:
Where:
i
is the
limiti
setting (current limit)
•
measurei:
Sets the current measure range
•
measuredelay:
Defines the delay to wait after lowering the current limit before taking the measurement
Script example
Use the
smua.source.highc
attribute to set and control the options for high-capacitance mode,
charge a capacitor, and test for leakage.
The following programming example (and figure) illustrates how to enable high-capacitance mode on
SMU A.
1. To enable high-capacitance mode, send:
-- Enables high-capacitance mode.
smua.source.highc = smua.ENABLE
i
C
Δ
v
Δ
t
------
=
Содержание 2657A
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