USB-5684 Triggers

The USB-5684 supports internal and external triggering when you are using either time slot or scope acquisition modes. Internal triggers are based on the input signal you are measuring, and external triggers are based on the signal present on the external trigger input terminal.

After you configure the trigger type, you can configure the trigger source, slope, and a delay value. For internal triggers, you also can configure a trigger level and a value for trigger hysteresis.

Optimizing Internal Triggering

Sometimes it can be difficult to obtain consistent triggering. Here are some points to consider when choosing triggering parameters:

  • Signals that slowly vary with time can include noise in the signal channel. This noise can result in false triggers. To avoid false triggering in this situation, try setting the trigger level at a power higher than the bottom of the measurement range.
  • Modulated signals can appear noisy and may also result in false triggers. In this situation, adjusting the trigger level may not improve the false triggering. Instead, try using a different trigger point and adjusting the trigger delay to shift the waveform in time to a portion of the signal with less modulation or less “noise-like” modulation.
  • Always optimize the trigger settings before you apply trace averaging. If you use trace averaging when the trigger is not stabilized, the displayed waveform is not an accurate representation of the signal.