The USB design separates data and power for safer, faster, and cleaner connections from factories to hospitals. See more!
The CN0590 is a galvanic isolation reference design for USB 2.0 high-speed Type-C connectors from Analog Devices (ADI). It provides a fully isolated connection between a USB 2.0 host and a USB 2.0 device, offering signal and power isolation up to 2.5 W and supporting data rates up to 480 Mbps as per the USB 2.0 standard. The design meets 2.5 kV rms isolation voltage per UL 1577, with a creepage and clearance (C&C) distance of 3.1 mm, and complies with IEC 61010, IEC 62368, and IEC 60601 requirements for industrial, instrumentation, energy, and medical applications.
Data isolation is implemented using the ADuM3166, and power isolation is achieved through the ADuM3070 driver with an external transformer. The ADuM3070 delivers regulated isolated power of 5 V at up to 2.5 W with higher stability and efficiency than unregulated converters, operating up to 105°C. The isoPower circuitry generates isolated power for the secondary side, while the primary side is powered directly from the USB Type-C input cable — requiring no external supply. According to USB 2.0 high-power specifications, ports must supply 4.75 V to 5.25 V and at least 500 mA, which the ADuM3070 meets.
An additional USB Type-C receptacle on the secondary side of the isolation barrier allows powering external loads requiring more than 2.5 W. Two MAX14606 devices manage dual power sources, prioritizing the external supply when available and providing reverse polarity, overvoltage, and overcurrent protection.
Galvanic isolation in USB connections is important for breaking ground loops, improving resistance to common-mode transients, and ensuring noise immunity, reducing signal integrity problems. It is also required for safety compliance under standards like IEC 62368-1 (IT and A/V products), IEC 61010-1 (measurement and control equipment), and IEC 60601-1 (medical devices). These prevent fire hazards and protect users from high-voltage faults. In medical systems, isolation ensures patient safety when connecting non-certified IT equipment to patient-connected devices such as imaging or surgical systems, or when using applied parts like USB 2.0 cameras.
In industrial settings, isolation prevents electromagnetic interference (EMI) from machinery such as motor drives or welding equipment, reducing the risk of system malfunction and protecting operators and equipment from high-voltage faults. It can also improve signal-to-noise ratio (SNR) in high-end audio applications.
USB is a standard from the USB Implementers Forum and is one of the most widely used point-to-point serial interfaces, often replacing RS-232 in industrial debugging and firmware upgrades. It supports simple, hot-swappable connections and power delivery. The USB 2.0 protocol is half-duplex and supports three speeds: 1.5 Mbps (low speed), 12 Mbps (full speed), and 480 Mbps (high speed).
ADI has tested this reference design. It comes with a bill of materials (BOM), schematics, assembly drawing, printed circuit board (PCB) layout, and more. The company’s website has additional data about the reference design. To read more about this reference design, click here.
