Digital Isolation Technology

Analog Devices µModule (micromodule) isolated transceivers provide robust galvanic isolation for digital serial communication interfaces, including SPI, I2C, RS-485/RS-422, RS-232, and USB. Isolation barriers are implemented using Ethernet transformers, coupling capacitors, or embedded inductors. All devices are simple to configure, have very low EMI susceptibility and emissions, and feature high noise immunity to preserve signal integrity. Our µModule^® (power module) technology helps reliably integrate inductive/magnetic isolation, discrete components, ICs, and power onto a single substrate PCB. Any application, from signaling to sampling, can be supported by the platform. Our technology achieves isolation up to 3500 V rms, and is consistently rugged and reliable.

Analog Devices’ family of isolated I²C isolators support a complete isolated I²C interface. This portfolio is based on our iCoupler^® chip scale transformer technology. iCoupler is a magnetic isolation technology with functional, performance, size, and power consumption advantages compared to optocouplers. By integrating iCoupler channels with semiconductor circuitry, our technology enables a complete, isolated I²C interface with a small form factor. Our I²C isolators covers applications such as central office switching, networking, and power over Ethernet.

As the world’s leading supplier of data converters, Analog Devices is constantly introducing new A/D converters (ADCs) that drive system architectures. In the motor control arena, ADI’s converters solve the challenges associated with current and voltage monitoring, optical encoder feedback, and resolver-to-digital conversion. The introduction of the isolated ADC with its 3.75 kV standoff voltage is one example of ADI’s breakthroughs in performance and integration to ease the burden of design.

ADI isolated controller area network (CAN) transceivers provide the differential physical layer interface between the data layer link, hardware protocol (for example, embedded in some of ADI's Blackfin^® processors), and the physical wiring of the CAN bus. ADI's portfolio includes transceivers with integrated iCoupler^® and isoPower^® isolation, providing, fully isolated off-the-shelf CAN PHY's.

Analog Devices small form factor isolated gate drivers are designed for the higher switching speeds and system size constraints required by power switch technologies such as SiC (silicon carbide) and GaN (gallium nitride), while still providing reliable control over switching characteristics for IGBT (insulated gate bipolar transistor) and MOSFET (metal oxide semiconductor field effect transistor) configurations for high-side and low-side switches. These isolated gate drivers leverage ADI’s proven iCoupler isolation technology combined with high speed CMOS and monolithic transformer technology to enable ultralow propagation delay without sacrificing common-mode transient immunity (CMTI) performance. High pulse fidelity architecture enables motor power efficiency to meet new required efficiency levels, and superior timing performance stability reduces voltage distortion, as well as harmonic and output power content on solar inverters.

Isolated LVDS (low voltage differential signaling) devices couple differential signals applied to the LVDS receiver inputs across the isolation barrier to the outputs on the other side and re-transmits the bit stream or clock as LVDS. Analog Devices' drop-in LVDS isolators offer designers robust, high speed differential signaling for point-to-point and multidrop applications. Extending iCoupler^® chip scale transformer technology for ultrahigh speed data encoding, these LVDS isolators support a a data rate of up to 2.5 Gigabits per channel for a total bandwidth of 10 Gbps. In contrast to expensive fiber implementations, deserialized links over standard digital isolators or optocouplers, and design-intensive bespoke solutions using transformers or high voltage capacitors, ADI Gigabit Digital LVDS isolators offer the only integrated comprehensive, high performance isolation at 10 Gbps. High performance galvanic isolation for applications include analog front-end (AFE), processor to processor serial communication, or video and imaging data (such as HDMI isolators) as well as isolation between boards, or at a cable interface for LVDS or CML signal chains.

Isolated RS-232 is a serial communication standard defined by TIA/EIA-232-F that conveys data over a simple unterminated, multiconductor cable. Although the original specification was intended for modems, subsequent RS-232 transceivers support general-purpose serial interfaces at data rates up to 1 Mbps. Analog Devices offers a wide range of isolated iCoupler^® and μ‎Module^® RS-232 transceivers that remove ground loops by isolating the logic-level interface and line transceiver, protect against voltage spikes and common-mode transient events so data remains intact, and provide options for integrated dc-to-dc power converters. iCoupler digital isolation technology solutions minimize PCB real estate and enable the power isolation and signal isolation required for system reliability in a noisy environment. μ‎Module RS-232 transceivers offer isolated RS-232 solutions with no external components and up to 1 W of additional power.

RS-485 is a multipoint communication network defined by the TIA-485-A/EIA-485-A standard that specifies up to 32 drivers and 32 receivers on a single (2-wire) bus, with modern transceivers improved to allow 256 nodes on the same bus. The differential signaling scheme and wide common-mode tolerance provide excellent noise immunity for high speed communication over long distances and in harsh environments. Analog Devices’ RS-485/RS-422 compliant transceivers support industrial fieldbus, Modbus and PROFIBUS®, process control networks (PLC), building automation (HVAC), and motor control servo drives and encoder applications. Connect with half- or full-duplex models and options that include extended temperature, ultralow skew, enhanced drive strength, full fail-safe and hot swap support, low voltage logic interfaces, integrated termination, and extensive EMC protection against IEC surge, EFT, ESD, and overvoltage faults for the design of RS-485 communication links.

Isolation Amplifiers provide power supply designers with a higher performing, single chip alternative to isolation techniques based on optocouplers and shunt regulators. Analog Devices ADuM3190 and ADuM4190 isolated error amplifiers have a 400 kHz bandwidth, with 0.5% typical initial accuracy at 25°C and 1% total accuracy over the extended temperature range of –40˚C to +125˚C. This provides manufacturers of ac-to-dc and dc-to-dc power supplies with a significant upgrade in speed and operating temperature range, as well as a 5× improvement in transient response.

Analog Devices isoPower^® technology utilizes proprietary iCoupler^® chip scale transformers to integrate isolated dc-to-dc converts with data isolation into a single package. This enables designers to implement isolation in designs without the cost, size, power, performance, and reliability constraints found with optocouplers. With more than one billion channels shipped into the field, these magnetically isolated products are a safe, reliable and easy-to-use alternative to optocouplers.

SPI (Serial peripheral interface) is one of the most widely used interfaces between microcontrollers and peripheral ICs such as sensors, ADCs, DACs, shift registers, SRAM, and others. Analog Devices has your isolated SPI bus covered with our dedicated SPI digital isolators which support this synchronous, full duplex master-slave-based interface. Options include devices built with ADI's proven iCoupler® technology and offering a small footprint, simple design-in, fast speeds, and high data integrity, as well as integrated µModules which require no external components. Our SPI isolator solutions increase performance and reduce board space. This simple, compact solution is ideal for isolated SPI data requiring communication across different ground potentials or through large common mode transients often found in Industrial PLCs (programmable logic controllers) and Instrumentation and data acquisition systems.

Analog Devices’ digital isolators enable designers to implement robust solutions with our magnetically isolated iCoupler products with the flexibility of up to 6 channels. Products meet stringent safety standards including the ability to isolate IS-IS with our intrinsically safe certified digital isolators which enable designs in hazardous areas. And automotive certified versions are also available. Utilizing the iCoupler^® and isoPower^® technologies, these isolation solutions enable designs without the constraints found in optocouplers.

USB isolators protect the communication interface between the host, such as a PC, and its peripheral. Utilizing iCoupler® digital isolation technology, Analog Devices offers USB 2.0 compliant SOIC components with data rates up to 12 Mbps that provide EMC protection and safety isolation, reduce design size and time, and lower system cost. Galvanically isolated USB μModule® (micromodule) transceivers integrate the USB interface with an isolated dc-to-dc converter for up to 2.5 W of isolated power and provide ±15 kV ESD. Whether for host, hub, bus splitter, or peripheral device, these transparent USB digital isolators are easy to use—they just work—all while meeting the demanding standards required for medical and industrial applications.