The source unit can output configurable voltage pulses or current pulses.

Pulsing in Single Point Source Mode

In Single Point source mode, the source unit generates a single pulse, then returns to the pulse bias level.

Figure 2. Single Pulse Cycle

Graph showing pulse cycle with on time, off time, and bias level.

The following steps illustrate the typical operation of the source unit for each pulse when you initiate a pulse output function.

  1. To enable pulsing, set NI-DCPower Output Function to Pulse Voltage or Pulse Current.
  2. (Optional) In Sequence source mode, if this step is not the first step in a sequence, the source unit emits a Ready For Pulse Trigger event. Then, the source waits for a Pulse Trigger.
  3. After receiving the Pulse Trigger, the source unit applies the pulse level configuration. In Sequence source mode, the pulse level is the next pulse level in the array.
  4. After waiting the time specified by the source delay, the source unit generates a Source Complete event. If you set the source delay for each step in Sequence source mode, this time is the subsequent source delay in the array.
  5. (Optional) To configure the measure unit to take a measurement and store it in a buffer on the device, set NI-DCPower Measure When to Automatically After Source Complete.
  6. Once the pulse on time elapses, the source unit applies the pulse bias configuration.
  7. After waiting the pulse bias delay, the source unit emits a Pulse Complete event.
  8. The source unit waits the remainder of the pulse off time.
  9. At commit, the bias settings are applied to the output.

Pulsing in Sequence Source Mode

In Sequence source mode, the source unit uses a list of pulse levels one after another, while maintaining the specified duty cycle. It does this by applying the defined Pulse On and Pulse Off times.. The following figure illustrates a sequence consisting of two pulses. The sequence is repeated twice.

Figure 3. Sequence with Two Pulses

Graph showing a sequence of two pulses with triggers and delays.
Note Timing properties for pulses, such as pulse on time, pulse off time, and pulse bias delay, must be constant for every step in the sequence.

Pulsing in an Advanced Sequence

Pulsing in an advanced sequence differs from pulsing in sequence source mode. The diference is because you can reconfigure all pulse-related properties per step in an advanced sequence.

Pulse Source Model

Table 3. Properties Applied for Each Pulse Output Function
Pulse Voltage Pulse Current
Pulse Voltage Level Pulse Current Level
Pulse Bias Voltage Level Pulse Bias Current Level
Pulse Voltage Level Range Pulse Current Level Range
Pulse Current Limit1 Pulse Voltage Limit1
Pulse Current Limit High2 Pulse Voltage Limit High2
Pulse Current Limit Low2 Pulse Voltage Limit Low2
Pulse Bias Current Limit1 Pulse Bias Voltage Limit1
Pulse Bias Current Limit High2 Pulse Bias Voltage Limit High2
Pulse Bias Current Limit Low2 Pulse Bias Voltage Limit Low2
Pulse Current Limit Range Pulse Voltage Limit Range

1Applied when NI-DCPower Compliance Limit Symmetry is Symmetric.

2Applied when NI-DCPower Compliance Limit Symmetry is Asymmetric.

The following properties are applied for both pulse output functions:
  • Source Delay
  • Pulse Bias Delay
  • Pulse On Time
  • Pulse Off Time

Support for Pulsing

The following devices do not support pulsing.

  • PXI-4110
  • PXIe-4112/4113
  • PXI-4130
  • PXI-4132
  • PXIe-4140/4141/4142/4143/4144/4145
  • PXIe-4154
  • PXIe-4162/4163