Chipanalog Isolated Interfaces

Isolated communication interfaces provide several benefits: Protection against ground loops and common-mode voltage differences

Immunity to electrical noise in industrial environments

Safety isolation between high-voltage and low-voltage circuits

Protection from lightning and surge transients

and Reliable communication over long distances. In industrial systems, different nodes may have significant ground potential differences. Isolation prevents these differences from affecting communication and protects sensitive control electronics.

Use isolated interfaces for industrial networks or long-distance communication. Contact our FAE team for interface selection.

Non-isolated CAN uses a single transceiver connected directly to the bus. Isolated CAN adds a digital isolator between the CAN controller and transceiver, plus isolated power supplies. Key differences: Isolated CAN eliminates ground loops between nodes

Isolated CAN provides protection against high-voltage transients

Isolated CAN requires separate isolated power for the transceiver side

and Isolated CAN has slightly higher cost but much better reliability. For industrial applications with multiple nodes or long bus lengths, isolated CAN is strongly recommended.

Use isolated CAN for multi-node industrial networks. Contact our FAE team for CAN design guidance.

Isolated CAN transceivers require two power supplies: VCC1 (logic side): 3.3V or 5V for CAN controller interface

VCC2 (bus side): 5V for CAN transceiver, isolated from VCC1. Options for isolated VCC2: Use isolated DC-DC converter module

Use CA-IS37xx with integrated DC-DC

or Use transformer-coupled isolated supply. The isolated supply must provide sufficient current for the transceiver (typically 50-100mA). Place decoupling capacitors (0.1μF + 1μF) close to VCC2 pin.

Use integrated DC-DC for simple designs. Contact our FAE team for isolated power solutions.

Important bus protection features for isolated interfaces: ESD protection (>8kV contact discharge)

Overvoltage protection (±58V for RS-485)

Short-circuit protection (current limiting)

Thermal shutdown (overtemperature protection)

and Fail-safe features (defined output during faults). Chipanalog isolated interfaces include comprehensive protection: ±16kV ESD protection

±58V fault protection on bus pins

Current limiting and thermal protection

and Open-circuit and short-circuit fail-safe. These protections ensure reliable operation in harsh industrial environments.

Select interfaces with comprehensive protection. Contact our FAE team for protection requirements.

Yes, isolated interfaces support standard data rates: Isolated CAN: Up to 1Mbps (CAN 2.0B) or 5Mbps (CAN FD)

Isolated RS-485: Up to 20Mbps or higher

Isolated I2C: Up to 1MHz Fast Mode Plus. The isolation barrier adds minimal delay (typically 10-20ns), which is negligible compared to bit times at standard rates. For example, at 1Mbps CAN, bit time is 1μs, so 20ns isolation delay is only 2% of bit time. Isolated interfaces are fully compatible with non-isolated devices on the same bus.

Isolated interfaces support standard rates. Contact our FAE team for high-speed applications.