Understanding the function, characteristics, principle, classification and selection of signal isolators (II)

Signal isolator features:

1.Highly compact, ultra-thin

The 12.5mm thickness allows the product to be densely installed in the control cabinet, saving cabinet space and reducing cabinet costs.

2.High precision and reliable electrical isolation

≤0.1% transmission error, isolated voltage with up to 2.5kV guarantees signal transmission accuracy and product reliability.

3.Easy to use, maintain

The product supports bottom bridge power supply, which reduces wiring work and saves cable cost. At the same time, it supports isolator hot swap for post-maintenance. In-line measurement technology can measure current signal without cutting off the loop; integrated in 12.5mm thickness range Terminal is a pluggable technology isolator that can easily break the wiring loop.

4.Clear instructions

Each signal isolator incorporates a separate LED indication that clearly indicates the current operating state of the isolator.

5.Wide area power supply and operating temperature

Support 9.6-31.2V DC flexible power supply, -40~80 °C wide operating temperature.

6.Latest digital isolation technology

At present, most signal isolators use optocouplers to meet the isolation requirements. Changhui signal isolators have adopted CMOS digital isolation technology. From the technical side, there are still significant differences between optocouplers and digital isolation:

Simply put, a photocoupler is a hybrid device that uses light from an LED to transmit data to a photodetector at the other end of the barrier. In the logic high state, the LED is turned on, and when the logic is low, the LED is turned off. Optocouplers are high power, prone to aging and temperature, and offer limited data rates, typically less than 1 Mb/s. However, digital isolation devices are created to meet safety regulations while maximizing the benefits of modern CMOS technology. To this end, digital isolation devices use semiconductor process technology to create transformers or capacitors to transfer data rather than transmit light, and by using this technology, performance and functional integration are improved.

Optocouplers, although incorporated into many designs, are based on outdated LED technology, whose output varies significantly due to input current, temperature, and aging. This reduces the performance of the device over its lifetime. Digital isolation components make it easy to provide a multi-channel isolation solution that occupies less space, improves system reliability due to lower failure rates, and provides twice the electrical noise immunity over a wider temperature range (-40°C) Working within ~125 ° C) and does not age or degrade performance over time. In general, the use of high frequency carriers instead of light enables low operating power and high speed operation, which supports accurate timing specifications.

7.High stability and reliability

The functional safety design concept runs through the whole process of hardware design, software design and production management of Changhui isolator products, so that the products meet the requirements of relevant safety integrity levels, and maintain high precision, high reliability and long service life in many years of continuous operation.