Diodes Inc. Unveils Dual-Channel Digital Isolators for High Voltage Systems

Recently, Diodes Inc. launched the API772x series within its RobustISO family, a line of dual-channel digital isolators, marking the beginning of the company’s portfolio of isolation devices. These devices are designed for high-voltage systems such as industrial automation, new energy systems, and data centers, which require reliable and robust isolation for digital signals.

High-voltage applications like industrial automation, solar power, and data centers need reliable isolation for their digital signals.

Understanding the Need for Digital Isolators

High-voltage power architecture is becoming more common across electric vehicles, renewable energy systems, and industrial automation, which leads to increasing challenges related to noise immunity, safety, and long-term reliability. 

Traditional isolation technologies, such as optocouplers, often fail to maintain signal fidelity, particularly in fast-switching power stages using wide-bandgap semiconductors like SiC and GaN, which generate rapid voltage transients that older devices cannot reliably handle. 

Therefore, engineers now require isolators that are capable of withstanding high dv/dt switching, maintaining signal integrity, and providing long-term operation without performance degradation. Digital isolators meet these demands by providing a compact, robust, and reliable solution for critical applications.

Key Specifications of the API772x Family 

The API772x digital isolators from Diode Inc.’s RobustISO family offer dual-channel digital isolation optimized for high-voltage systems. These isolators are designed to meet basic and reinforced isolation requirements in accordance with various standards such as VDE, UL, and CQC. They offer an isolation rating of  5 kVRMS for one minute per UL 1577 and an 8 kVPK rating per DIN EN IEC 60747-17 (VDE 0884-17), along with a breakdown voltage over 12.8 kVPK.

A capacitive isolation barrier of thickness greater than 25 µm is used in these devices. Data is transmitted through the barrier using an ON-OFF keying (OOK) modulation scheme, which ensures long term reliability, with a predicted operation lifetime exceeding 40 years. 

The devices use an ON-OFF Keying (OOK) modulation scheme.

The devices support data rates of up to 100 Mbps and have a minimum 150 kV/µs common-mode transient immunity (CMTI). These new isolators operate over a wide supply voltage range of 2.5 V to 5.5 V, consume minimal current, typically 2.1 mA per channel at 1Mbps, and feature a low propagation delay of approximately 11ns, ensuring timely communication between isolated domains.

The API772x family includes six variants, offering flexibility in channel-direction configurations and default output levels. The “F” suffix denotes devices configured with a LOW default output at power-up, whereas non-suffix variants default to a HIGH output. The devices are packaged in a compact SO‑8W (Type CJ) form factor, making them suitable for space-constrained applications. More information about the RobustISO family can be found in the API772x datasheet.

Distinctive Features and System Advantages

One of the standout features of the API772x dual-channel digital isolators is their minimum 150 kV/µs CMTI. This high CMTI rating ensures that fast voltage transients do not disrupt signal transmission across the isolation barrier. This leads to reliable communication, reduced risk of data errors, and improved overall system stability in environments prone to electrical noise.

The use of SiO₂-based capacitive barrier resists breakdown even under high-voltage stress. Together, the reinforced isolation rating and the use of a durable dielectric material maintain consistent electrical separation, ensuring long-term reliability and a predicted operational lifetime exceeding 40 years.

The combination of high data rates, low propagation delay, and low power operation, along with a compact SO-8W package, makes these isolators well-suited for space-constrained applications such as electric vehicles, battery management systems, and renewable energy inverters. Dual-channel integration further simplifies PCB layouts and reduces component count, enabling efficient, high-performance system design.

Meeting the Need Long Term Digital Isolation

The API772x series sets a benchmark for reliable, long-lived digital isolators in high-voltage and new energy systems. As power electronics continue to adopt faster switching and compact architectures, devices like the RobustISO family are likely to become a standard choice for electric vehicles, energy storage, and renewable power applications.

All images used courtesy of Diodes, Inc.