R&S enters eight-channel oscilloscope game

The Rohde & Schwarz MXO 5 series of eight-channel and four-channel oscilloscopes feature fast capture and low-level triggering so you can see signal details.

There was a time when we had to live with just two oscilloscope channels. Today, four channels are common but that’s not often enough. That’s where eight-channel oscilloscopes can help. With the MXO 5 series, Rohde and Schwarz enters the eight-channel oscilloscope market. While R&S trails competitors in entering the eight-channel market, the company makes up for it with fast waveform updates, high resolution, and low-level triggering. For engineers who don’t need eight analog channels, the MXO 5 is available with four channels.

The MXO 5 series features 12-bit resolution with an 18-bit HD mode. That drops the number of channels from eight to four or four to two, depending on the model. Signal bandwidths are 100 MHz, 200 MHz, 350 MHz, 500 MHz, 1 GHz, and 2 GHz for eight-channel models. The four-channel models exclude the two lower bandwidths. Bandwidth is field upgradeable.

All models come with 500 Msamples of acquisition memory per channel with options for 1 Gsamples per channel. The actual amounts of memory per channel depends on acquisition mode. That is, an eight-channel instrument has 500 Msamples/ch with eight active channels when running a single capture. When running continuously, you get 500 Msamples/ch with four active channels. When using the four-channel instrument, you get 500 Msamples/ch both when running in single-capture mode and when running continuously. Samples rates: 5 Gsamples/sec on four channels or 2.5 Gsamples/s on eight channels.

Since their inception, digital oscilloscopes have suffered from “dead time” because of the processing time to show waveforms on a screen, also called screen update rate. That dead time has continuously shrunk as more powerful processors have become available. The MXO 5 series dead time is just 1%, meaning you can see the waveforms 99% of the time because it can process 4.5 million waveforms per second.

The oscilloscope’s processing power extends to displaying signals in the frequency domain. Because the MXO 5 can process 45,000 fast-Fourier transforms (FFTs) per second, you can see both time-domain and frequency-domain plots simultaneously.

The high resolution of the MXO5 lets you see small-signal differences such as ripple on a power rail. To get a stable view, you need to trigger on the ripple or other characteristics of waveforms. Many oscilloscopes have complex triggers that can help. The MXO 5 goes a step further, using what Rohde & Schwarz calls a high-precision digital trigger. The company claims that this patented trigger is 10,000 times more sensitive than those on competing oscilloscopes. The trigger also lets you acquire waveforms based on signal-level differences that are just 0.01 of a screen division.

Even if you can trigger an oscilloscope on ripple or power-supply glitches, you need to understand how those characteristics can affect your circuits. That’s where the power-analysis option can help. That option, combined with FFTs and current probes, lets you see harmonics and other conditions that can affect power delivery.

To achieve such low-level triggers means the signal of interest must still appear above the noise. To accomplish that, the MXO 5’s noise level is just 130 µV at 1 mV/div at the full bandwidth of 2 GHz.

The MXO 5 series has a 15.6-in touchscreen display. If that’s not large enough, you can connect a larger display through the oscilloscope’s HDMI port. For remote control, you can connect the unit to a computer using its LAN or USB Type-A posts. In addition, the MXO 5 contains four USB host ports for connecting flash drives or for powering and communicating with devices under test such as IoT devices or semiconductor evaluation boards.