Keithley 4200-SCS Reference Manual page 226

Section 6: Keithley Interactive Test Environment (KITE)
• Sweep forcing-functions (displayed only in the Sweeping test mode)
- The Current Sweep forcing function
- The Voltage Sweep forcing function
• List-sweep forcing functions (displayed only in the Sweeping test mode)
- The Current List Sweep forcing function
- The Voltage List Sweep forcing function
• Step forcing functions (displayed only in the Sweeping test mode)
- The Current Step forcing function
- The Voltage Step forcing function
NOTE
Power On Delay
When an ITM test is run, the SMUs for the given test power-on in a specific sequence. The first
SMU in the sequence powers-on immediately.
Power-on delays can be set between all the SMUs in the test. The set delay for an SMU occurs
after it powers-on, assuming there is another SMU in the power-on sequence.
For example, assume there are three SMUs in a test and the power-on sequence is SMU1, SMU2
and SMU3. Also assume that the power-on delay for SMU1 is set to 50 ms and the delay for SMU2
is set for 100 ms. When the test is started, the power-on sequence for the SMUs will be as follows:
SMU1 powers-on > 50 ms delay > SMU2 powers-on > 100 ms delay > SMU3 powers on
For Each SMU in the test, the Power On Delay field in the Forcing Functions / Measure
Options window is used to set this delay, which can be set from 0 to 0.100 s.
The power-on sequence for the SMUs is set from the ITM Timing window that is launched by
clicking the Timing button at the top of the ITM Definition tab. See
section
Pulse Mode
To avoid device overheating in some tests, voltages or currents can be applied to a device only for
brief periods at widely spaced intervals. For sweep (linear, log and list) and bias forcing functions,
an SMU can be set to provide pulse output. With Pulse Mode enabled, the following pulse
parameters can be set: On Time, Off Time and Base Voltage (or Base Current). The base is the
level the SMU goes to between sweep points. Pulse on and off times determine pulse period and
pulse width as follows:
Pulse period = On Time + Off Time + cumulative measure time (if set to measure)
Pulse width = On Time
Pulse Mode can be selected ONLY when source and measure ranges are fixed. In other words,
Pulse Mode is disabled if the source or measure range is set to AUTO.
Pulse on and off times can be set from 5 ms to 10 s. The base voltage (or current) that can be set
is dependent the present source range (Src Range).
An example pulse output for the Voltage Bias forcing function is shown in
output goes to the specified pulse level during the pulse on time. If the SMU is set to measure, the
measurement will occur after the on time expires and before the transition to the off time level. This
effectively increases the on time by the amount of time required to make the measurement.
6-100
The Forcing Function combo box is used to assign, as well as display, forcing
functions. Refer to Assigning/reassigning forcing functions to the device terminals
earlier in this section.
for details.
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Model 4200-SCS Reference Manual
Timing window later in this
Figure 6-123. Pulse
4200-901-01 Rev. S / May 2017