Keithley 2635 Reference Manual

8-22 Return to Section Topics 2600S-901-01 Rev. C / January 2008
Section 8: Source-Measure Concepts Series 2600 System SourceMeter® Instruments Reference Manual
Pulse concepts
Using factory scripts, the Series 2600 can perform fixed, linear staircase, and logarithmic staircase
pulse sweeps (see “
"Pulse sweeps"” in Section 5 for more information). The following paragraphs
discuss pulse period, rise and fall times, and duty cycle. See the specifications in Appendix A for
details on source transient response and settling times. Additional settling time considerations are
discussed in “
"Settling time considerations"” later in this section.
Pulse period
As shown in Figure 8-16, the pulse period is the sum of the pulse on time (pulse width) and the
pulse off time. When the pulse is off, the output assumes a 0V or 0A level, depending on the
function used. When the pulse is on, the output assumes the programmed current or voltage
source value. For the fixed pulse sweep, the amplitude of each pulse is the same. For the
staircase sweeps, each pulse assumes the programmed sweep step value. Pulse on and off times
can be separately programmed for each type of pulse sweep.
Figure 8-16
Pulse period
Pulse Period
0V or 0A
Off-Time
Pulse Width
(On-Time)
Pulse rise and fall times
As shown in Figure 8-17, the pulse rise time is the interval it takes the pulse to go from 10% of
maximum value to 90% of maximum value. For the Series 2600, pulse rise and fall times depend
on the transient response and source output settling times, which are in turn affected by the
selected source range. See the specifications in
Appendix 8 for details on transient response and
source settling times.
Figure 8-17
Pulse rise and fall times
0V or 0A
90%
10%
Rise
Time
Fall
Time
Times Exaggerated
For Clarity
Programmed Fixed
or Sweep Step Level

Keithley 2635 Specifications

General

Brand	Keithley
Model	2635
Category	Measuring Instruments
Language	English