Section 3: Functions and features Series 2600B System SourceMeter® Instrument Reference Manual3-28 2600BS-901-01 Rev. B / May 2013Timers must be used to configure the pulse width and period. Refer to Using timers to perform pulsemode sweeps (on page 3-45) for details.The pulse width is managed by controlling the duration between the source stimulus event and theend pulse stimulus event. Note that a latency exists between these stimulus events and their resultingsource level transitions. This trigger latency can vary based on factors such as the source range andthe electrical characteristics of the device under test (DUT). The fast ADC mode can be used tocharacterize this latency, in order to better control the shape of the pulse under a particular set of testconditions.The figure below shows the source and end pulse stimulus events in relationship to the pulse (seeTriggering (on page 3-32) for information for information on stimulus events). Any change in ∆t willresult in a corresponding change in the pulse width.Figure 61: Pulse width controlPulse duty cycleDuty cycle is the percentage of time during the pulse period that the output is on. It is calculated asfollows:Duty cycle = Pulse width / (Pulse width + Off time)For example, if the pulse width is 10 ms and the off time is 90 ms, the duty cycle is calculated asfollows:Duty cycle = 10 ms / (10 ms + 90 ms)= 10 ms / 100 ms= 0.10= 10 percentSee Maximum duty cycle equation (on page 4-3) for additional information on calculating themaximum duty cycle for a SMU.
