Digital Isolators

SI8645BA-B-IU is a non-isolated ac-operated relay driver with over-temperature and over-voltage protection. It is designed to drive one or two channels of telecom-class relays. It is a high power driver designed for use in telecom, industrial, multi-channel systems, and many other applications.

Application Field

SI8645BA-B-IU is widely used in telecom and other related industries, industrial automation, telecommunication equipment, multi-channel systems, high power relay systems, etc. The device offers very low power consumption and high-efficiency current control capability, making it well-suited for multiple design applications.

Working Principle

SI8645BA-B-IU works mainly by providing a switching signal to drive the transistor switch, which in turn will control the current flow across the load. The output is regulated by the input voltage of the device, and the signal propagation speed will be limited by the output transistor current. The output transistor will switch on and off as necessary to protect the load from over-voltage and over-temperature, and thus the current is controlled. Additionally, the SI8645BA-B-IU will internally protect itself from over-current and over-voltage conditions. The device also includes a built-in driver, so the driver circuit can be made quite small enough for space saving. Additionally, the onboard bias control can be used to vary the switching time, providing further flexibility for the designer.