Modern digital oscilloscopes can capture massive amounts of data. This can be both a blessing and a curse.
Traditional test and measurement tools make it difficult to trigger on the event that was looked for. It is difficult to tell what information is present by looking at the analogue signal and it is a time consuming and error prone process to have to manually decode a long period of bus activity to diagnose problems.
The Tektronix DPO3000, DPO4000 and MSO4000 Series of Digital Phosphor Oscilloscopes's strong trigger, decode and search capabilities enable today’s design engineers to solve embedded system design issues with efficiency.
Furthermore, the Wave Inspector system gives the user the tools to extract the answers needed with efficiency.
One of the key specifications of an oscilloscope is record length. Record length is the number of samples an oscilloscope can digitise and store in a single acquisition.
The longer the record length, the longer the time window the oscilloscope can capture with high timing resolution (high sample rate).
The first digital oscilloscopes could capture and store only 500 points, which made it difficult to acquire all relevant information around the event being investigated.
Designers were constantly faced with a choice of either acquiring a longer period of time at low resolution or a shorter period of time at high resolution, when what they really wanted was both: a long capture window and high resolution.
As designs become faster and more complex, the need for long records, more bandwidth, and higher sampling rate, will also increase. The relationship between these key specifications is not complex.
As bandwidth goes up, the sampling rate must be approximately five times higher to accurately capture the signal’s high frequency content.
As the sampling rate goes up, a given time window of signal acquisition requires more samples. For example: to capture 2 milliseconds of a 100 MHz signal at 5 GS/s requires a 10 million point record (divide 2 milliseconds by the 200 picosecond sample interval).
Even at lower frequencies there are many applications that require long records. Just capturing a single frame of PAL video (two fields in a 1/25th of a second interval, at 100 MS/s to resolve all the luminance information) requires 4 million points (40 milliseconds divided by 10 nanoseconds).
Capturing several seconds of bus traffic on a 1Mb/s CAN bus to diagnose problems in an electro-mechanical system may require 10 million points for adequate resolution.
These and a variety of other applications have driven and continue to drive the need for longer and more detailed data capture windows.
As time went by and technology progressed, the speed, ease and cost of digitising more detail became more favourable. However, at the same time, overall system design complexity became higher.
Clock speeds rose and bus topologies evolved through both wider and faster parallel designs as well as a shift towards serial buses.
Some of the reasons contributing to the shift are less board space required due to fewer signals to route, lower cost, lower power requirements, fewer pins on packages, embedded clocks, differential signalling for better noise immunity and wide availability of components using standard serial interfaces.
While serial buses provide a number of advantages, they also pose some significant challenges to an embedded system designer due simply to the fact that information is being transmitted in a serial fashion rather than parallel.
One solution is the Tektronix Digital Phosphor Oscilloscopes Series.
The user can see more and solve faster with the recently launched Tektronix DPO3000 Series of oscilloscopes.
The Wave Inspector system controls combined with a widescreen display helps to quickly search, navigate and see more horizontal on-screen data, glitches that might otherwise have missed can be caught.
And when it comes to serial debug, the user can trigger, decode, and search on a host of common standards including I2C, SPI, CAN, LIN, and more.
The user can debug faster and easier with Tektronix DPO4000 Series Wave Inspector's ability to zoom, pan, play, pause and set marks - helping to efficiently navigate through long serial data records.
This makes the Tektronix DPO4000 Series of oscilloscopes a suitable choice when working with today's common serial buses, such as I2C, SPI, RS-232/422/485/UART, CAN, LIN and FlexRay.
The MSO4000 Series combines all the features of the DPO4000 oscilloscope with logic analyser functionality.
Its familiar oscilloscope operation, large display and innovative user-friendly features have been designed to make work easier.
TekMark Australia are authorised Australian distributors for all Tektronix electronic test and measurement and monitoring solutions.