Mixed-Signal Oscilloscopes with New In-Vehicle Serial Bus Options

Yokogawa (the Netherlands) has added new trigger and analysis options to its DLM2000 (4-channel) and DLM4000 (8-channel) mixed-signal oscilloscopes (MSOs) for testing the latest generation of in-vehicle serial buses. The new options are specifically designed to address the measurement challenges posed by the CAN FD (CAN with Flexible Data Rate) and SENT (Single Edge Nibble Transmission) bus systems.

CAN FD is a higher-speed version (up to 8 Mbit/s) of the original CAN Bus designed to provide a faster, more reliable and cost-effective solution to the challenge of the increased amount of data traffic in automotive applications such as firmware updating for ECUs (electronic control units).

SENT is a point-to-point scheme for transmitting signal values from a sensor to a controller. It enables high-resolution and composite data transmission with a lower system cost in applications such as angle sensors for power steering and mass air flow sensors for engine control. SENT can replace existing analogue or PWM signal transmission, and is considered to be cost-effective compared to other serial buses such as CAN/LIN.

When equipped with the new serial bus options, the Yokogawa MSOs will decode the bus signals and display the results in real time. A wide variety of dedicated triggers and search functions are available to aid analysis and troubleshooting on parameters that can affect the bus signals: something that is becoming increasingly important as the amount of traffic inside the CAN bus grows with more sophisticated vehicle control systems.

The Yokogawa DLM Series of oscilloscopes are ideally suited to this type of analysis because of the versatility provided by their long memory: in particular, the length of the acquisition memory in Yokogawa's DLM4000 mixed-signal 8-channel oscilloscope is up to 250 Mpoints, making it a straightforward task to handle the extended data frames used in the CAN FD bus that allow the bit rate inside a frame to be changed flexibly. It also makes it possible to display trend data over extended periods: up to 100 seconds of data for SENT signals with microsecond duration, for example.

The DLM2000 is a 4-channel mixed-signal oscilloscope with bandwidths from 200 to 500 MHz and memory up to 250 Mpoints. Channel four can be activated either as an analogue input, or to acquire 8 bits of logic. The DLM4000 is an 8-channel MSO available in both 350 MHz and 500 MHz models, with 2.5 GS/s sampling. It features eight analogue input channels, with the eighth input channel converting to an 8-bit logic analyser at the push of a button. An additional 16 logic analyser inputs are available as an option, for 24-bit logic analysis.