World's fastest USB oscilloscope?

Alex Mendelsohn

eeProductCenter (11/29/2006 10:24 AM ET)

St Neots, England—Instrument maker Pico Technology unveils its PicoScope 5204, a dual-channel PC-connected digital sampling oscilloscope with a bandwidth of 250 MHz. The 5204 also gives you a memory depth of 128-Msamples and a realtime sampling rate of 1-Gsample/s.

According to Pico Technology, other scopes in the 5204's price range force you to compromise on one of three key specs; either sampling rate, bandwidth, or memory depth.

In contrast, the PicoScope 5204 claims to outstrip 'em all in all three of these areas. Pico bills its scopes as a no-compromise instrument that's priced at a point that virtually every engineer can afford. The 5204 is available now, priced at about $3500.

Your PC will need to run a Pentium II processor, or equivalent Pico suggest a 2-GHz Pentium 4 with 256 Mbytes of RAM, but a slower Pentium with 64 Mbytes of memory will also serve. The PC can run Microsoft Windows 98SE, Windows ME, Windows 2000, or Windows XP.

Streaming Data

In use, the 5204 connects to a USB 2.0 (Universal Serial Bus) port of any Windows laptop or desktop PC. Once connected, you get a host of features, including advanced triggering and an equivalent-time sampling mode that can boost the sampling rate to 20-Gsample/s for repetitive waveforms.

With a USB streaming capability at speeds of up to 6-Msamples/s, the scope can be used for high-speed data acquisition; it can record huge sequences of gap-free data, limited only by the memory of your PC. It can stream across the USB connection to RAM or a hard disk drive.

Other functions include a built-in 250-MHz spectrum analyzer, and a 12-bit 125-Msample/s arbitrary waveform generator that can generate standard waveforms from a library of stored waveforms, including sine, square, triangle, ramp-up, ramp-down, sin(x)/x, Gaussian, half sine, white noise, and DC level. You can also define your own waveforms.

For its part, the spectrum analyzer lets signals up to 250 MHz be viewed in the frequency domain. A range of settings give you control over the number of spectrum bands, window types, and display modes.

Windows Software

The PicoScope 5204 is supplied with PicoScope 6, the latest release of Pico's oscilloscope software. This version takes advantage of your PC to provide high-end oscilloscope features with an easy-to-use Windows interface.

Click for larger typical screen image

New features in this software include a waveform buffer that automatically records the last 32 waveforms, and a so-called probe manager that includes support for custom probes such as current clamps. The probe manager lets you define your own probes, even those requiring non-linear corrections.

Automated Measurements

PicoScope 6 can also display automated measurements. These can range from a simple multimeter-style voltage readout, to advanced statistical and monitoring functions.

Tools include a pair of rulers for each axis that can be dragged onto the screen to make simple measurements of time, amplitude and frequency. You also get an axis dragging tool. Using it, the vertical axis of each channel in each view can be adjusted by clicking on the axis values and dragging the axis up or down. This feature is useful when data from one channel is obscuring data from another channel.

There are also zoom, panning tools, browsing, and zooming tools. These include a marquee zoom tools that lets you draw a box around an area you wish to magnify. A waveform replay tool uses a circular waveform buffer that automatically records the last 32 waveforms, enabling scrolling and replaying of data. That can come in handy when trying to find an intermittent event.

A Milestone

According to Alan Tong, Managing Director of Pico Technology, this PicoScope is a major milestone for his company. "With this level of performance, a PC scope can now be seen as a direct replacement for some benchtop scopes," says Tong.

"Most benchtop oscilloscopes at this price are crippled by having tiny buffer memories of 10,000 samples or less," adds Tong, "but the Picoscope offers a 128-million samples. That means the scope can capture complex waveforms at long timebases without a drop in sampling rate."

Vertical Or Horizontal

The 5204 is also housed so it can be placed either vertically or horizontally, in order to take up a minimum of desk space.

When used for mobile applications, the PicoScope 5204 is small enough to be carried in the same bag as a laptop. Supplied with a handy carrying case, the unit includes switchable probes, a power supply, software, and documentation.

Drivers and examples are supplied for popular programming languages, as well as third-party applications such as LabVIEW, VEE, and Excel. What's more, software updates are available free of charge for the lifetime of the product from Pico Technology's Web site.

Also available is a PicoScope 5203 version, with a 32-Msample buffer. It's priced at about $2330.

Click here here for a 4-page technical brochure (in Adobe Acrobat .PDF format).

Click here here to view a summary table of specs.

For more details contact Pico Technology Ltd., The Mill House, Cambridge St., St Neots, PE19 1QB England. Phone: +44 (0)1480 396 395. Fax: +44 (0)1480 396 296.

Pico Technology, 44 (0) 1480 396 395, www.picotech.com