Analog Devices Inc. ADUM2251WARWZ

Overview

ADUM2251WARWZ from Analog Devices is a hot-swappable, dual-channel digital isolator with one bidirectional I²C channel (SDA1/SCL1) and one unidirectional clock channel (SCL2), rated for 5 kV rms isolation, 3.0–5.5 V supply operation, and 1000 kHz I²C data rate. It enables isolated communication between microcontroller-based host systems and peripheral devices in power supplies and industrial control interfaces.

For engineers reviewing the ADUM2251WARWZ datasheet, ADUM2251WARWZ pinout, ADUM2251WARWZ application, or ADUM2251WARWZ equivalent, key selection considerations include its asymmetric I²C channel configuration (bidirectional SDA + unidirectional SCL), 105°C extended temperature rating, reinforced insulation compliance per DIN EN IEC 60747-17 (VDE 0884-17), and open-drain interface compatibility with standard I²C buses.

Technical Context

The ADUM2251WARWZ implements iCoupler® chip-scale transformer isolation to split bidirectional I²C signals into dedicated unidirectional magnetic channels-Side 1 uses modified input thresholds (700 mV logic low) and open-drain outputs, while Side 2 provides full I²C-compliant logic levels (0.3×VDD2 input threshold, 30 mA sink), enabling interoperability with standard peripherals. Its hot-swap circuitry prevents bus glitches during live insertion by enforcing undervoltage lockout until both VDD1 and VDD2 exceed 2.5 V and stabilize for ≥40 µs.

It delivers 25–35 kV/µs common-mode transient immunity, 645 V_PEAK reinforced working voltage (VIORM), and supports capacitive loads up to 40 pF on Side 1 and 400 pF on Side 2-enabling robust operation in noisy industrial environments with minimal external components.

Key Specifications

Pinout & Package

ADUM2251WARWZ is housed in a 16-lead SOIC wide-body package (RW-16), with 7.8 mm minimum creepage and clearance, RoHS-compliant, and rated for 125°C maximum junction temperature.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar I²C isolation applications.

Compared with ADUM2251WARWZ, ADUM2250ARWZ offers symmetric bidirectional capability at lower temperature grade, while SI8602AC-B-IS trades hot-swap robustness for marginally lower propagation delay but requires additional design effort to prevent bus faults during live insertion.

Availability

ADUM2251WARWZ is available at Aetrix Electronics and suitable for industrial power supplies, automotive battery management systems, and medical infusion pump designs requiring stable component supply, AEC-Q100 qualification, and reinforced 5 kV isolation.

Supply support for ADUM2251WARWZ 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 leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The ADUM2251WARWZ belongs to Analog Devices' iCoupler® digital isolator product line, engineered specifically for reliable, low-latency, high-CMTI isolation of I²C, SMBus, and PMBus interfaces in safety-critical and high-noise environments.

FAQ

What is the maximum operating temperature of the ADUM2251WARWZ?

The ADUM2251WARWZ is rated for operation from −40°C to +125°C ambient temperature, with the "W" suffix indicating automotive qualification and extended thermal performance beyond the standard −40°C to +105°C grade. This enables use in under-hood automotive applications and high-temperature industrial power converters where thermal derating must be minimized.

Does the ADUM2251WARWZ support true bidirectional communication on both I²C lines?

No - the ADUM2251WARWZ implements one bidirectional channel (SDA1/SCL1 on Side 1) and one unidirectional clock output (SCL2 on Side 2). This architecture is optimized for master-slave topologies where the isolated side only receives clock signals. For fully bidirectional clock/data on both sides, the ADUM2250 series is required.

How does the hot-swap functionality of the ADUM2251WARWZ prevent I²C bus glitches?

The ADUM2251WARWZ incorporates undervoltage lockout circuitry that holds all outputs high until both VDD1 and VDD2 exceed 2.5 V and remain stable for ≥40 µs. This ensures the isolator remains inactive during power-up transients, eliminating false START/STOP conditions or bus contention when inserting a powered card into an active backplane.

Can the ADUM2251WARWZ be used with 3.3 V logic on Side 1 and 5 V logic on Side 2?

Yes - the ADUM2251WARWZ supports independent 3.0–5.5 V supplies on each side. Side 1 operates at 3.3 V (VDD1 = 3.3 V) with logic thresholds referenced to its own supply, while Side 2 can run at 5 V (VDD2 = 5 V) with full 30 mA sink capability and I²C-compliant 0.3×VDD2 input thresholds, enabling seamless level translation.

What safety certifications apply to the ADUM2251WARWZ package variant?

The ADUM2251WARWZ uses the RW-16 SOIC wide-body package and is certified to UL 1577 (5000 V_RMS), IEC/EN/CSA 62368-1 (reinforced insulation, 390 V_RMS), IEC/CSA 60601-1 (2 MOPP, 125 V_RMS), and DIN EN IEC 60747-17 (VDE 0884-17) with VIORM = 645 V_PEAK, making it suitable for medical, industrial, and automotive safety-critical designs.