New Industry Products

Quad-Channel Digital Isolators Combine Safety, Isolation and Low Latency

February 03, 2024 by Jake Hertz

The Novosense digital isolators combine robust safety and isolation with low latency for high-speed applications.

Applications such as automotive, industrial, and medical are increasingly dependent on both low-voltage control electronics and high-power systems. Digital isolation has become necessary in these spaces to ensure interoperability between these different power domains and prevent damage to low-power electronics.


Digital isolator.

Digital isolator. Image used courtesy of Novosense


Novosense has released a family of quad-channel digital isolators designed specifically for these applications. This article examines the role of digital isolators and the details of the Novosense isolators.


Understanding Digital Isolators

A digital isolator is a common component in modern electronic systems. As a protective barrier separating and transmitting digital signals between system sections while maintaining electrical isolation, digital isolators are crucial for safeguarding sensitive electronic components from harmful high voltages and currents.


Typical PWM isolation application circuit for the NSi824x.

Typical PWM isolation application circuit for the NSi824x. Image used courtesy of Novosense


Digital isolators serve two main purposes: protection and signal integrity. They protect user interfaces and low-voltage domains from potential high-voltage hazards in industrial, medical, or automotive environments. Additionally, they prevent noise and transient voltages, common in industrial settings, from interfering with delicate digital signals, thereby maintaining signal integrity.

Digital isolators can achieve isolation through various technologies, such as capacitive, magnetic, and optical coupling. The choice of technology generally depends on factors like data rate requirements, power consumption, and environmental conditions. For instance, capacitive isolators are often preferred for their high-speed data transfer capabilities and low power consumption, making them suitable for high-performance industrial control systems.

These components are widely used in many applications. For example, in industrial applications, where equipment often operates at high voltages, digital isolators shield control units and data acquisition systems from these voltages, thus preventing damage and ensuring accurate data transmission. Similarly, isolators are crucial for patient safety in medical equipment, keeping high-voltage elements of devices like MRI machines or X-ray equipment isolated from patient-monitoring systems.


The NSi824x Family of Digital Isolators

The NSi824x series of quad-channel digital isolators consists of the NSi8240, NSi8241, and NSi8242 models.

One of the key features of the series is its capacity to handle data rates up to 150 Mbps while maintaining a common-mode transient immunity of up to 250 kV/us. Along with a low propagation delay (under 15 ns), this ensures high-speed data transfer and resilience against common electrical disturbances. The series is also designed for low power consumption, drawing just 1.5 mA per channel at 1 Mbps, which is crucial for energy-sensitive applications. 


Functional block diagram of NSi824x family members.

Functional block diagram of NSi824x family members. Image used courtesy of Novosense


The devices are engineered to deliver high reliability and safety, meeting stringent standards such as UL1577 certification. They support multiple insulation withstand voltages (3k Vrms, 3.75k Vrms, 5k Vrms, 8k Vrms) and have robust electromagnetic compatibility (EMC), including high chip-level ESD (±8kV).

Given the robust reliability and safety measures designed for the chip, it targets applications such as industrial automation equipment and motor control.


Looking Forward at Digital Isolators

As systems become more complex and the demands for efficiency and safety rise, the role of advanced digital isolators will only become more central. The NSi824x family provides engineers with a balance of speed and safety to meet the most stringent performance and compliance requirements in industrial applications.