Scopes enable flexible input configuration

Article By : Martin Rowe

Tektronix's MSO5 series allows users to select any input as analog or logic channels, enabling them to mix and match and change configurations as needed.

Debugging embedded systems and circuit power is often an exercise in having enough analog or digital outputs. Tektronix Inc. has released their MSO5 series of mixed-signal oscilloscopes, which the company claims gives customers the felixibility to choose between analog or logic inputs.

Available with four (Model MSO54), six (Model MSO56), or eight (Model MSO58) 12-bit (16-bit in high-res mode) analog inputs, the MSO5 series is ready to compete with Teledyne LeCroy's HDO series and the Rohde & Schwarz RTO2000.

Figure 1: The MSO5 series comes in 4, 6, or 8 input channels.

The MSO5's flexible inputs let you configure any input as one analog or 16 logic channels. Thus, you can mix and match and change the configuration as needed. Figure 2 shows the probes connected to the instrument. In this case, channels 1 and 2 are analog while channel 3 provides 16 logic inputs. The unused channel 4 input shows the analog connector as well as a set of contacts for the logic inputs.

Figure 2: With the right probe, any channel of the Tektronix MSO5 series can operate as one analog or 16 logic inputs.

The MSO5 series oscilloscopes have bandwidths of 350MHz, 500MHz, 1GHz, and 2GHz (Figure 3). Any model can operate at any bandwidth because they're upgradeable. You can upgrade with a license code up to 1GHz. For 2GHz, you need to bring the instruments to an authorised service centre.

Figure 3: Table of MSO5 series models.

At a pre-release demonstration, Tektronix claimed to have redesigned the MSO5 user interface based on the MSO5 series capacitive touchscreen display. As you'd expect, it provides pinch gestures for adjusting time and voltage scales. It also lets you add channels from the screen and create math channels using drag and drop movements. When you add a channel, each appears in a separate grid and uses the entire ADC dynamic range (Figure 4).

Figure 4: The MSO5 series defaults to placing each channel in a separate grid. It does let you overlay them when you need to compare signals.

The MSO5 series still has knobs, for eliminating them altogether would be a mistake, but it lacks dedicated knobs for each channel. That's one way to get the large 15.6-in. display to fit. Note that each channel shown in Figure 1 has a colour bar associated with that channel. That colour is also the channel's trace colour, plus the common vertical knob changes colour depending on which channel you use. Figure 5 shows the colours for Ch 2 (left) and Ch 3 (right). Competitor Rohde & Schwarz uses the same concept with its oscilloscopes.

Figure 5: A lighted ring around the vertical knob indicates the selected channel. Hopefully, your eyes can distinguish all of them.

The MSO5 series can operate using internal firmware, but it has an option for running Windows. An SSD (solid-state drive) inserts from the bottom of the case, letting the oscilloscope run under Windows 10. You can then install any Windows app such as math, signal processing, and games. You must purchase the SSD from Tektronix to use Windows. You can remove the SSD and move it to another MSO5-series oscilloscope and go back to running the internal software.

Even if you don’t use Windows, you can still perform jitter analysis on the many supported serial buses. That's because the MSO5 series includes DPOJET, a jitter-analysis app, embedded in the software.

In designing the MSO5 series, Tektronix put some thought into simple things such as the legs. The MSO5 series have legs at both the front and back of the case, which lets you place it on a shelf above the bench and tilt it downward for easy viewing. The front legs have a locking mechanism that prevents them from folding inward when the rear feet are in use. Figure 6 shows a front leg sill extended even with the unit tilting forward. A spring-loaded mechanism pushes up from the weight of the unit, locking the leg in extended position. To fold the leg, simply lift the unit's front; the foot will pop out and you can then fold it.

Figure 6: The MSO5 series has locking front legs that prevent them from folding down when the oscilloscope is tilted forward.

The table below shows base prices of the MSO5 series.

Figure 7: MSO5 series pricing.

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