Analog Devices Introduces Four-Channel, Single-Package Products For Data & Power Isolation
Analog Devices, Inc. (ADI) is expanding its family of digital isolation products with a series of four-channel devices that isolate both data and power. Each device integrates ADI’s ICoupler digital isolation technology and ADI’s proprietary isoPower™ dc-to-dc converter, providing both isolated power and isolated signal channels within a single package.
The ADuM540x ICoupler digital isolators with isoPower are described as a better choice over discrete solutions, such as optocouplers with external dc-to-dc converters, because it is claimed that their small 10 x 10mm surface mount packages can reduce board space by up to 70% and cut costs by as much as 50%. In addition, the ADuM540x devices come with safety pre-approvals, which is said to allow designers to realize faster design times as compared to discrete-based solutions, which require time-consuming safety approvals that can delay time-to-market.
"Delivering 500mW of isolated power in a small, surface mount package, the ADuM540x products enable customers to put more channels of isolation into space-constrained designs at reduced cost," said Ronn Kliger, Product Line Director, Digital Isolation Products, Analog Devices. "For example, industrial control designers can now increase the number of isolated data ports in a single control module without increasing the size of the module, even though each port requires its own isolated power supply. With alternate solutions, such as optocouplers and separate, isolated dc-to-dc converters, the control module would need to increase in size and would not be backward compatible with installed industrial control systems."
The on-board isoPower isolated dc-to-dc converter provides up to 500mW of regulated, isolated power and can operate at either 5.0 or 3.3V. A version with two channels (ADuM520x) and a version that features only the isoPower isolated power supply (ADuM5000) will be released later this year.
With more than 150 million channels deployed throughout the industry, ADI’s ICoupler technology is based on chipscale transformers, rather than on the LEDs and photodiodes found in optocouplers. Transformers can support higher data rates and lower power consumption, and are more stable over life as compared to LEDs and photodiodes. By fabricating the transformers directly on-chip using wafer-level processing, it is claimed that the ICoupler channels can be integrated with each other and other semiconductor functions at low cost.
ICoupler transformers are planar structures formed from CMOS and gold metal layers. A high breakdown polyimide layer underneath the gold layer insulates the top transformer coil from the bottom. CMOS circuits connected to the top coil and bottom coil provide the interface between each transformer and its external signals.
ICoupler digital isolators condition and drive data across transformers. ADI’s isoPower dc-to-dc converter uses the same chipscale transformer technology, but instead of transmitting data, isoPower employs switches, rectifiers, and regulators to generate power that is isolated to the same degree as the data channels.
The ADuM540x family of four-channel digital isolators, including the ADuM5401, ADuM5402, ADuM5403 and ADuM5404, are available now, and the ADuM5400 will be available in July 2008. Housed in a 16-lead wide-body SOIC (small-outline integrated circuit) package, the ADuM540x family is priced at $5.00 per unit in 1,000-unit quantities. The ADuM520x family and ADuM5000 are priced at $4.08 and $3.16, respectively, per unit in 1,000-unit quantities. These devices will be available in July 2008.
