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Industrial applications often require high speed SPI buses when interfacing to various sensors. These applications may further require galvanic isolation for enhanced robustness. But when designing such an isolated SPI bus, simply choosing a digital isolator based on the guaranteed data rate isn’t sufficient.  The propagation delay of the isolator – rather than the data rate – actually constrains the throughput of the interface. However, this isn’t a concern in non-isolated SPI solutions because PCB trace delays are very small relative to the clock period.  So, wouldn’t it be great if we could design an isolated SPI interface with minimal speed limitations introduced by the isolators? Isolated SPI could now be run as fast as its non-isolated counterpart and at the same time be simple to design. Read our article to explore an integrated solution that allows isolated SPI to run as fast as 40MHz, while optimizing for power, size, design-time and cost.

Controller Area Network (CAN), standardized under ISO 11898, is widely used in industrial and automotive applications. CAN protocols such as DeviceNet or CANOpen rely on the built-in error checking and differential signaling. Galvanic isolation can further enhance robustness, offering immunity to high voltage transients at a cost of added propagation delay. Optimal configuration of CAN nodes can allow the maximum data rate and distance even when isolation is present. Read Dr. Conal Watterson's complete article to learn more.

Optocouplers have traditionally been used to isolate potentially dangerous voltages in many types of electrical equipment. Today, more modern digital isolators based on transformer or capacitive coupling are widely used. Transformer-based digital isolators offer many benefits such as improved performance, integrated functionality, lower power dissipation, better longer-term reliability, and improved ease of use.



This article will discuss international and regional standards that have been developed to ensure uniform specification and testing of isolator components and systems. It will review digital isolators that meet the superset of international and regional standards—including 10 kV surge testing—to provide maximum flexibility to equipment vendors in meeting these varying requirements.



Have you considered digital isolators to meet your reinforced insulation requirements?


Isolation has been considered a necessary burden by designers.  It is necessary because it makes electronics safe for anyone to use. It is a burden because it limits communication speed and consumes a lot of power and board space.  Old-technology optocouplers and even many, newer digital isolators consume so much power that that certain types of applications have not been practical.  This article examines the latest developments in ultra low power isolation, how it relates to the available technologies, and how it has been achieved.

RS-485 Sniffer using ezLINX

Posted by hmarais Mar 27, 2013

Troubleshooting RS-485 serial interfaces can be done by using the ezLINX™ iCoupler®  isolated interface development environment as a Sniffer. This is achieved by connecting the board to the USB port of your PC and connecting it to the PC Application. Instructions on the initial setup of the board can be found on the ezLINX wiki:


Once the board is connected to your PC And you can communicate to it, click on the “RS485” button on the top left of the Application. This opens the RS-485 Configuration Window.


Setup your baud rate and RS-485 settings to the settings of the bus you want to debug

  • Baud rate
  • Parity
  • Stop bits
  • Number of data bi
  • Half duplex or full duplex


Click on the use changes button. This will configure the Isolated RS-485 port to the desired settings and will open a window that will allow the user to transmit or receive data on the communications port through using the ADM2587E signal and power isolated RS-485 transceiver. Connect the RS-485 bus that needs to be debugged to connector J7 and configure the jumpers as required. For more information please see User Guide UG-400.


You should now be in a position to receive any messages on the RS-485 bus. Ensure that you have selected the correct Data format(ASCII/Hexadecimal).

The primary function of an isolator is to pass some form of information across an electrical barrier while preventing current flow. Isolators are constructed from an insulating material that blocks the current flow, with a coupling element on both sides of the barrier. Information is typically encoded before being transmitted across the barrier by the coupling elements.


iCoupler® digital isolators from Analog Devices use chip-scale micro-transformers as the coupling element to transfer data across a high quality polyimide insulation barrier. Two primary methods of data transfer have been used in iCoupler isolators: single-ended and differential. Selection of a data transfer scheme involves engineering trade-offs to optimize the desired characteristics of the end product.


Read More Here.


Isolated CAN networks will have an increased propagation delay over nonisolated CAN networks, and it can often be challenging to design.  The linked example, shows an isolated CAN node using the ADM3053 signal and power isolated CAN transceiver for calculating the necessary CAN controller parameters to communicate at 1 Mbps over a 20 m cable. Learn more here.


Some other links you might find of interest:


Isolated Transceivers


An Alternative to Optocouplers -


iCoupler Digital Isolator Products -

Systems that require isolation often need to isolate both data paths and power supplies. To simplify such designs and to reduce area, Analog Devices recently released the ADuM347x family of iCoupler digital isolators. These products integrate four channels of high speed data isolation with a transformer driver and secondary PWM controller that can be used to implement an isolated push-pull dc-to-dc converter. Integrating the elements of an isolated power supply into the same package as the data isolation significantly reduces the number of components and reduces the overall design complexity. To achieve this, the ADuM347x incorporates ADI’s proprietary iCoupler technology to produce a two-chip solution in a 20-lead SSOP package.  Learn more here.


Some other links you might find of interest:


An Alternative to Optocouplers -


iCoupler Digital Isolator Products -