Analog Devices Inc. ADUM3481ARSZ-RL7

Overview

ADuM3481ARSZ-RL7 from Analog Devices is a quad-channel digital isolator using iCoupler® transformer-based isolation, providing 3.75 kV_RMS reinforced insulation, 25 Mbps data rate, and 1.8 V to 5 V level translation across isolated domains. It features independent core (3.0–5.5 V) and I/O (1.8–5.5 V) supplies, output default select via CTRL pins, and operates up to +125°C - deployed in industrial SPI isolation and fieldbus interfaces.

For engineers reviewing the ADuM3481ARSZ-RL7 datasheet, ADuM3481ARSZ-RL7 pinout, ADuM3481ARSZ-RL7 application, or ADuM3481ARSZ-RL7 equivalent, key selection criteria include its 20-lead SSOP package, dual-supply flexibility, 25 ns typical propagation delay, high CMTI (>25 kV/µs), and compliance with UL 1577, VDE 0884-17, and IEC 62368-1 safety standards.

Technical Context

The ADuM3481ARSZ-RL7 implements four unidirectional isolation channels with side-specific control: Side 1 has inputs A–C and output D, while Side 2 has input D and outputs A–C - enabling asymmetric signal routing. Its monolithic air-core transformer architecture eliminates LED aging and timing drift inherent in optocouplers.

It supports dual-supply operation: core supplies (VDD1/VDD2 = 3.0–5.5 V) power internal logic and regulators, while I/O supplies (VDDL1/VDDL2 = 1.8–5.5 V) drive input thresholds and output levels - allowing 1.8 V logic interfacing without level shifters. Default output states are programmable per side via CTRL1 and CTRL2 pins.

Key Specifications

Pinout & Package

ADuM3481ARSZ-RL7 uses a 20-lead, 0.150" wide, RoHS-compliant SSOP package with 0.65 mm lead pitch. Thermal resistance θ_JC = 50.5°C/W. Input-to-output resistance is ≥10¹² Ω; capacitance is 2.2 pF at 1 MHz.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar digital isolator applications.

Compared with SI8641ED-IS and ISO6741QDWR, ADuM3481ARSZ-RL7 uniquely supports true 1.8 V I/O interfacing with programmable default outputs and integrated regulator outputs - making it optimal for legacy industrial systems requiring robust, low-voltage, fail-safe isolation without redesigning power architecture.

Availability

ADuM3481ARSZ-RL7 is available at Aetrix Electronics and suitable for industrial PLCs, motor drives, solar inverters, and medical auxiliary power supplies requiring stable component supply, long-term lifecycle support, and certified reinforced isolation.

Supply support for ADuM3481ARSZ-RL7 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. is a global semiconductor company specializing in high-performance analog, mixed-signal, and digital signal processing technologies for precision instrumentation, industrial, and communications markets.

The ADuM348x family was designed specifically for cost-sensitive, high-reliability industrial isolation applications requiring extended temperature range, low-power operation, and regulatory-certified reinforced insulation - targeting SPI, RS-485, and gate driver interfaces.

FAQ

What is the maximum data rate supported by ADuM3481ARSZ-RL7?

ADuM3481ARSZ-RL7 supports up to 25 Mbps non-return-to-zero (NRZ) data rate, verified across all operating conditions (−40°C to +125°C) and supply configurations (1.8 V to 5 V I/O). This enables full-speed SPI clocking at 12.5 MHz with two edges per bit, meeting timing requirements for high-resolution ADCs and fast DACs in industrial control systems.

Does ADuM3481ARSZ-RL7 support 1.8 V logic on both sides of the isolation barrier?

Yes, ADuM3481ARSZ-RL7 supports 1.8 V I/O operation on both sides: VDDL1 and VDDL2 accept 1.8 V to 5.5 V, enabling direct connection to 1.8 V FPGAs or microcontrollers. Core supplies VDD1/VDD2 require 3.0–5.5 V, but internal regulators (VDDC1/VDDC2) provide stable bias - confirmed in Tables 7–9 of the Rev. B datasheet.

How does the output default select function work on ADuM3481ARSZ-RL7?

ADuM3481ARSZ-RL7 uses CTRL1 (Pin 7) and CTRL2 (Pin 14) to set default output states during power-up or input loss: low = default low, high = default high. This ensures fail-safe behavior in motor control (e.g., disable gate drivers on reset) and avoids floating states in fieldbus transceivers - a feature absent in most competing isolators.

What safety certifications apply to ADuM3481ARSZ-RL7?

ADuM3481ARSZ-RL7 is certified to UL 1577 (3750 V_RMS, 1 min), VDE 0884-17 (reinforced, VIORM = 560 V_peak), IEC/EN/CSA 62368-1, and IEC/CSA 61010-1. These approvals are production-tested per Table 11 and Table 13 - confirming suitability for industrial equipment with functional safety requirements up to SIL 2.

Can ADuM3481ARSZ-RL7 replace optocouplers in existing designs without layout changes?

ADuM3481ARSZ-RL7 is pin-compatible with industry-standard 20-lead SSOP footprints and offers superior timing (25 ns typical propagation delay vs. 100+ ns for optocouplers), lower power, and no LED aging. However, layout must maintain ≥5.3 mm creepage/clearance per Table 12 and avoid copper under the isolation barrier - minor adjustments may be needed for legacy optocoupler pads.