Tag Archives: Oscilloscopes

Oscilloscopes Lose their Faces

The word oscilloscope usually conjures up images of a box with a display. Earlier, oscilloscopes were bulky devices with a display made of a cathode ray tube, but later the models became sleeker, and came with a liquid crystal display. Another difference was in their method of measurement. Whereas there were analog units earlier, later models sported an analog to digital converter inside, which converted all analog signals to digital data. Nevertheless, the display continued to be a part of the oscilloscope.

However, Tektronix now has unveiled a low-profile oscilloscope that has lost its faceā€”the display. The MSO5 series of oscilloscopes from Tektronix has a faceless version aimed at Automated Test Equipment (ATE) applications. It is a low-profile version competing with modular oscilloscopes and digitizers.

Suitable for automated tests or for monitoring machines, the low-profile MSO58 of the MSO5 series, is a rack mountable unit. All its specifications match those of its regular benchtop cousins. It has eight analog inputs with FlexChannel features, which allow eight digital channels to substitute the analog channel with a 1-GHz bandwidth on all of them. The real-time scan rate for all the channels is 6.25 Gsamples/sec with 12-bit ADCs on each channel, but a high-resolution mode allows the resolution to increase to 16 bits and 125 Msamples/sec. That makes the effective number of bits as 7.6 at 1 GHz, or 8.9 at 20 MHz, with a record length of 125 Msamples/channel.

Software within the faceless oscilloscope can help with jitter and serial bus analysis, channel math and Fast Fourier Transformations (FFT). For bench and debugging applications, the software also provides cursors. There are six USB host inputs, on USB input for a device, a LAN port, a Display Port, DVI-D port, SVGA output port. However, the device lacks GPIB connectivity.

As the internal hardware and functionality is identical in both the benchtop and the faceless versions of the MSO5 series oscilloscopes, any automation code for production for device validation and characterization works interchangeably. The six USB host ports may lead one to believe the low-profile oscilloscope could be useful as a system controller. However, the operating system of the unit is a closed Linux version, and a separate PC is necessary for automated use.

The six USB device ports can help in creating a network, to which, one can add more accessories such as an external storage or other instruments. If you have additional MSO5 low-profile units to work together, you can also add a USB hub or an Ethernet switch. Unfortunately, for those using GPIB primarily, these units do not come with a GPIB port.

It is very easy to configure any input of the low-profile faceless oscilloscope as one analog or 16 logic channels. Therefore, one can mix and match the configuration to change it as necessary. For instance, channels 1 and 2 can be analog, while the channel 3 caters to 16 logic inputs.

Bandwidths for the MSO5 series oscilloscopes are 350 MHz, 500 MHz, 1GHz, and 2 GHz. However, one can upgrade any model at any time to operate at any bandwidth.