Keithley 2461 Reference Manual

Model 2461
Interactive SourceMeter® Instrument Reference Manual Section 8:
TSP command reference
2461-901-01 A/November 2015 8-217
Details
When the sweep is started, the instrument sources a specific voltage or current value to the device
under test (DUT). A measurement is made for each point of the sweep.
When the sweep command is sent, it clears the existing trigger model and creates a new trigger
model. To run the sweep, initiate the trigger model.
The sweep continues until the source outputs the specified stop level. At this level, the instrument
performs another measurement and then stops the sweep.
When you specify a delay, a delay block is added to the sweep trigger model. This delay is added to
any source delay you may have set. For example, if you set 10 ms for the source delay and 25 ms for
the delay in the for the log sweep command, the actual delay is 35 ms.
The range type specifies the source range that is used for the sweep. You can select the following
options:
• Auto: The instrument automatically goes to the most sensitive source range for each source level in the
sweep.
• Best fixed: The instrument selects a single fixed source range that accommodates all the source levels
in the sweep. This avoids overshoots during sweeps.
• Fixed: The source remains on the range that is set when the sweep is started. If a sweep point that
exceeds the capability of the source range, the source outputs the maximum level for that range.
The asymptote changes the inflection of the sweep curve and allows it to sweep through zero. You
can use the asymptote parameter to customize the inflection and offset of the source value curve.
Setting this parameter to zero provides a conventional logarithmic sweep. The asymptote value is the
value that the curve has at either positive or negative infinity, depending on the direction of the
sweep. The asymptote value must not be equal to or between the starting and ending values. It must
be outside the range defined by the starting and ending values.
Example
reset()
smu.source.func = smu.FUNC_DC_VOLTAGE
smu.source.range = 20
smu.measure.func = smu.FUNC_DC_CURRENT
smu.measure.range = 100e-6
smu.source.sweeplog("VoltLogSweep", 1, 10, 20, 1e-3,
1, smu.RANGE_FIXED)
trigger.model.initiate()
Reset the instrument to its defaults.
Set the source function to voltage.
Set the source range to 20 V.
Set the measure function to
current.
Set the current range to 100 µA.
Set up a log sweep that sweeps
from 1 to 10 V in 20 steps with a
source delay of 1 ms, a sweep
count of 1, and a fixed source
range. Name the configuration list
that is created for this sweep
VoltLogSweep.
Start the sweep.
Also see
Sweep operation (on page 3-53)
trigger.model.initiate() (on page 8-259)

Keithley 2461 Specifications

General

Maximum Current	7 A
Power	100 W
Resolution	6.5 digits
Source Measure Unit (SMU)	Yes
DC Voltage	100 V
Maximum Voltage	100 V
Display	5-inch capacitive touchscreen
Connectivity	USB, GPIB
Software	TSP
DC Current	7 A
Current Source Range	0 to 7 A
Voltage Measurement Range	100 mV to 100 V
Current Measurement Range	10 nA to 7 A
Voltage Measurement Resolution	100 nV