Infineon Technologies Launches New Chip-Scale Solid-State Relay with Coreless Transformer Technology

Infineon Technologies has launched a new solid-state relay (iSSI) series that uses coreless transformer technology to improve device performance and efficiency.

Infineon's coreless transformer. Image courtesy of Infineon

Infineon launches new solid-state relay

Infineon Technologies has designed a new family of solid-state relays to facilitate faster and more reliable circuit switching. According to the company, the devices offer a set of protection features that go beyond traditional optocoupler solid-state relays (SSRs).

For example, the newly launched solid-state relays support 20 times more energy transfer than previous generations. In addition, these relays have an RDS(on) 50 times lower than existing optocoupler solutions, enabling them to be deployed in applications that require higher voltages and powers. Infineon reports that iSSI provides better performance and reliability than electromagnetic relays by eliminating additional components, resulting in a 40% reduction in startup power.

Block diagram of the iSSI20R11H. Image courtesy of Infineon Technologies

Infineon said the new iSSI series is compatible with other products in the Infineon switch portfolio, including the CoolMOS S7, OptiMOS and linear FET portfolios. For example, when used with Infineon's CoolMOS S7 switch, the relay driver simplifies the switch design, with significantly lower resistance than optocoupler solutions. This means that the system has a longer service life and lower cost of ownership. In applications that drive the gate of Infineon's MOS-controlled power transistors, power consumption can be reduced by up to 70% compared to solid-state relays using silicon-controlled rectifiers (SCRs) and Triac switches.

Infineon's solid-state relays enable custom SSR configurations to control loads exceeding 1,000 V and 100 A. This capability, along with the device's coreless transformer technology, makes the relays ideal for use in advanced battery management systems, energy storage solutions, renewable energy systems, and industrial and building automation applications.

The key to solid state relays

Solid-state relays prevent unwanted current feedback in a variety of systems. This feature is critical in applications ranging from signal processing to power supply design, where maintaining the integrity and isolation of electrical signals is critical.

At the heart of a solid-state relay is the principle of achieving electrical isolation through semiconductor materials. Unlike mechanical relays or optocoupler relays, which may use switching elements or photodiodes as a means of achieving isolation, solid-state relays significantly improve reliability and reduce response time. For example, by employing methods such as capacitive or magnetic coupling within the semiconductor substrate, the relay can effectively block high-voltage transients while allowing the desired signal or power flow to pass unimpeded.

Example of electrical isolation

Solid-state relays offer many advantages over traditional electromechanical relays or photorelays. First, they have no switching parts, minimizing wear and tear, thereby extending service life and improving reliability. They also offer faster response times, which is critical for high-speed signal processing applications. In addition, solid-state relays offer improved performance in terms of size, efficiency, and noise immunity, making them ideal for miniaturized and sensitive electronic systems.

Finally, solid-state relays enhance the safety of electrical systems by providing superior isolation capabilities. This is especially important in medical devices, industrial control systems, and power grid applications, where it is critical to protect sensitive components and operators from high-voltage transients. The ability to integrate these relays into semiconductor chips also fits the trend toward more compact and integrated electronic systems.

Versatile Options for Custom Solid State Relays

With its new iSSI family, Infineon Technologies aims to provide engineers with tools that support more efficient, high-performance high-voltage and power supply designs. Thanks to the coreless transformer design and intentional design compatibility with other Infineon switch products, the new iSSI can effectively replace reed relays and electromechanical relays. Designers can combine iSSI with power switches as flexible circuit elements for custom solid-state relays.