How do I use the arbitrary function generator on the MDO3000?

Hello and welcome to Tektronix! Today I’m going to demonstrate the function generator capability on the MDO3000 mixed domain oscilloscope.

The MDO3000 contains an integrated arbitrary function generator (or AFG) that can output predefined or user-defined waveforms directly from the instrument. It can also capture a signal from one of the scope’s inputs, transfer the waveform data to the arbitrary waveform memory and output it from the AFG. Noise can also be added to any signal to easily perform margin testing.

The MDO3000’s AFG port is on the back of the scope. For this demo, I’ll be connecting a BNC cable from the AFG output to channel 1 on the front of the scope. To access the AFG functionality, simply press the AFG button below the bus buttons. You can change the waveform output function using the Waveform softkey and the multipurpose knob A. Once you’ve chosen the desired waveform type, you can configure the frequency and amplitude using the Waveform Settings softkey. You can change either the Frequency or Period using the multipurpose knobs or the keypad, and you can define the amplitude characteristics of the waveform using amplitude and offset or high and low, again using either the multipurpose knobs or the keypad . In the Output Settings menu, output impedance, noise, AUX Out function, and high-low levels can be configured.

The arbitrary waveform type is an incredibly powerful tool for simulating signals or adding noise to existing signals for margin testing. The arbitrary feature has a 128k point record length for copying or creating complex waveforms, and these waveforms can come from a variety of sources, including one of the scope’s inputs, the internal waveform editor, or Tektronix’s waveform editing software called ArbExpress. I’ll demonstrate capturing a waveform from one of the channels in this video. I’m connecting a probe to channel 2 of the scope and acquiring a digital signal from an SPI bus for replication. To capture this waveform, I’ll need to change the trigger to channel 2 rather than channel 1 where it’s currently set. I’ll perform a single capture so that the scope has acquired the waveform points. Press the AFG button, press the Waveform softkey, and select Arbitrary using the multipurpose knob A. Select the Waveform Edit softkey, select the Load Waveform softkey, change the Load From to channel 2 using Multipurpose knob A, and select OK Load. The AFG will now be outputting the exact signal that was captured on Channel 2 with the same frequency and amplitude, but these parameters can be changed as desired in the Waveform Settings menu.

Once you would have to use an entirely different instrument to get the AFG functionality, but it is now included, along with 5 other instruments, in the incredibly versatile MDO3000.