FAQs

ADM2682E - FAQ

What are the benefits of iCoupler technology?

iCoupler technology provides benefits in five key areas:

Integration benefits are provided by the ability to readily combine iCoupler channels with other semiconductor functions or to combine multiple iCoupler channels in a common package thereby reducing size and cost relative to optocoupler implementations. Performance benefits are provided in the form of increased timing accuracy, transient immunity, and data rates relative to optocoupler components. Power consumption benefits are provided in the form of 10-to-50 times lower power consumption as well as the accompanying reduction in thermal dissipation.

Ease-of-use benefits are provided by the elimination of many of the difficulties presented by optocoupler technology as well as the addition of new features that facilitate the use of iCoupler isolators in new designs. Optocoupler problem areas that iCouplers eliminate include their characteristic of widely-varying current transfer ratios, their LED wear-out phenomenon and the design burdens this imposes, and their need (in most optocouplers) to drive their input with high current to turn on the LED. Additional ease-of-use features that iCouplers provide include the ability to operate at reduced supply voltages, the ability to translate an input signal of one voltage into an output signal of a different voltage, the use of voltage-based digital interfaces, and the ability to operate over a wide temperature range.

Lastly, reliability benefits are achieved by the elimination of the LEDs contained within optocouplers. By using only standard CMOS process technology, iCoupler devices provide the same lifetime characteristics as other standard CMOS products.

What are the different types of iCoupler products?

iCoupler products are available in a variety of channel configurations and performance levels.

Products consists of single, dual, triple, and quad channel 2.5KVRMS and 5.0KVRMS isolators each available in multiple performance/price options. Products are also offered with other features including:

Please refer to the iCoupler web site (www.analog.com/iCoupler) for the most complete up-to-date selection table and other information about the iCoupler portfolio.

What regulatory standards address isolation products?

There are a wide variety of safety standards related to isolation at both the system and component levels, for various geographic regions, and for various applications. Shown below is a table summarizing commonly-used standards for the U.S., Europe, and International geographic regions.

Application U.S. Europe International
Industrial UL 508 EN 50178 IEC 604
Information Technology UL 1950 EN 60950 IEC 950
Medical UL 2601-1 EN 60601 IEC 601
Measurement and Control UL 3111 EN 61010-1 IEC 1010-1
Telecom UL 1459 EN 60950 IEC 950
Household UL 8730-1 EN 60065 IEC 65

Table 1. Application-Level Standards

Component U.S. Canada Germany/Europe International
Isolator UL 1577 Component Acceptance
Notice #5
DIN EN60747-5-2
DIN V VDE V 0884-10
IEC 747-5

Table 2. Component-Level Standards

The standards that apply directly to isolation components are those of Table 2. The standards of Table 1 apply to applications that use isolation components. The designer of such an application must assure that the appropriate isolation component is selected such that compliance with the relevant application-level standard is ensured. However, the application-level standard is not directly applicable to the isolation component. Only the standards of Table 2 are imposed directly at the component level.

What types of technologies have been used to provide isolation?

There are three common isolation technologies:

Each has benefits and disadvantages related to price, performance, reliability, size, features and functionality. Historically, optocoupler and transformer technologies have been the most commonly used methods.

What is transformer isolation?

Transformer isolation employs transformer coils to transmit information across an isolation barrier. Changes in current through the transformer winding on one side of the isolation barrier induce a corresponding current on the transformer winding on the other side of the isolation barrier. Transformer-based methods have been commonly used in applications involving AC signals (Ethernet, for example) that are well suited for transformer coupling. Transformer isolation has advantages in systems with high data rates, and it can also be used to provided an isolated power supply; however, transformers have typically been bulkier than alternative solutions.

iCoupler technology (see below) is a form of transformer isolation that employs micro-transformer coils to address the size and integration disadvantages of discrete transformer solutions.

What are common applications that use isolation?

Isolation is commonly found in applications involving high voltage, high-speed/high-precision communications, or communication over large distances. Common examples of such applications include:

These applications can be found in a wide range of markets, including:

Which iCoupler product is best for my application?

Due to the unique nature of each application, the choice of which product to use is best left to the user. The selection tables available at www.analog.com/iCoupler should provide guidance for choosing the most appropriate iCoupler product. For additional assistance, please contact your local Analog Devices sales representative or distributor.

Are iCoupler products Pb-free?

All iCoupler products are offered with Pb-free versions.

How do I learn about new iCoupler products?

Please visit the Analog Devices website at www.analog.com/icoupler for the most up-to-date information on new products. You may also contact your local Analog Devices Sales representative. A quarterly newsletter, "Analog Devices' Digital Isolation Update," is also available. The newsletter includes new product announcements as well as news, application tips and technical information about the iCoupler technology. Please refer to www.analog.com/Subscriptions to learn how to subscribe to the "Analog Devices' Digital Isolation Update."