Analog Devices Inc. AD8418AWHRZ

Overview

AD8418AWHRZ from Analog Devices is a bidirectional, zero-drift current sense amplifier optimized for high-side and low-side shunt-based current measurement in automotive motor and solenoid control. It delivers 20 V/V initial gain, ±200 μV max input offset over −40°C to +150°C, 90 dB min DC CMRR, −2 V to +70 V continuous common-mode input range, and 250 kHz small-signal bandwidth.

For engineers reviewing the AD8418AWHRZ datasheet, AD8418AWHRZ pinout, AD8418AWHRZ application, or AD8418AWHRZ equivalent, this page provides verified specifications, FMEA-tolerant 10-lead MSOP package details, bidirectional operation guidance, EMI-filtered PWM-compatible performance, and automotive-grade AEC-Q100 qualification context.

Technical Context

The AD8418AWHRZ employs a proprietary zero-drift architecture achieving 0.1 μV/°C typical offset drift and <400 nV/°C max drift across −40°C to +150°C, without sacrificing 250 kHz bandwidth. Its input stage incorporates integrated EMI filters and patented circuitry to maintain accuracy under fast PWM common-mode transients up to 1 V/ns.

It supports flexible output offset configuration via dual reference pins (VREF1/VREF2), enabling ground-referenced, supply-referenced, external-referenced, or ratiometric mid-scale (VS/2) operation. The device sustains −3 V to +80 V common-mode survival and operates from 2.7 V to 5.5 V supply with 4.2 mA max quiescent current.

Key Specifications

Pinout & Package

AD8418AWHRZ is housed in a RoHS-compliant, AEC-Q100 qualified 10-lead MSOP package (3.0 mm × 3.0 mm × 1.0 mm) engineered for failure mode and effects analysis (FMEA). This variant features NC pins inserted between critical signal pairs (−IN/GND and +IN/VREF1) to mitigate PCB short-fault propagation.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar current sense amplifier applications.

Compared with AD8418AWHRZ, AD8417ARWZ offers higher gain but sacrifices high-temperature capability, while INA240A1QDRQ1 extends common-mode range for 48 V systems but trades bandwidth for robustness-making AD8418AWHRZ optimal for demanding 12 V/24 V motor control requiring speed, precision, and extreme temperature resilience.

Availability

AD8418AWHRZ is available at Aetrix Electronics and suitable for automotive motor control, solenoid actuation, and high-side battery management requiring stable component supply, AEC-Q100 compliance, and extended temperature operation.

Supply support for AD8418AWHRZ 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, headquartered in Wilmington, MA.

The AD8418A product line delivers precision current sensing for safety-critical automotive subsystems, combining zero-drift accuracy, PWM immunity, and FMEA-aware packaging to meet ASIL-B design requirements in powertrain and chassis control.

FAQ

What is the maximum continuous common-mode voltage for AD8418AWHRZ?

The AD8418AWHRZ supports −2 V to +70 V continuous common-mode input voltage, with −3 V to +80 V survival rating. This allows reliable high-side sensing in 12 V and 24 V automotive systems during load-dump or cold-crank transients. The specification is validated across the full −40°C to +150°C operating range and applies directly to the AD8418AWHRZ device in its 10-lead MSOP package.

Does AD8418AWHRZ support true bidirectional current measurement?

Yes, AD8418AWHRZ supports true bidirectional current measurement via configurable output offset using VREF1 and VREF2 pins. When configured for mid-scale (VS/2) output at zero differential input, it delivers linear positive and negative output voltage excursions proportional to current direction and magnitude. This functionality is explicitly characterized and guaranteed for the AD8418AWHRZ across its full temperature and supply range.

Is AD8418AWHRZ pin-compatible with other AD8418 variants?

No, AD8418AWHRZ uses the 10-lead MSOP FMEA-optimized pinout, which differs from the 8-lead SOIC_N and 8-lead MSOP packages. Pin 1 (−IN), pin 3 (GND), pin 4 (VREF2), pin 6 (OUT), pin 7 (VS), pin 8 (VREF1), and pin 10 (+IN) retain functional equivalence, but the inserted NC pins (2, 5, 9) require unique PCB layout. This physical incompatibility is intentional for fault isolation and is documented in the AD8418A Rev. E datasheet Figure 3.

What is the purpose of the NC pins in the AD8418AWHRZ package?

The NC pins in AD8418AWHRZ (pins 2, 5, and 9) are strategically placed to isolate −IN from GND and +IN from VREF1, preventing PCB trace shorts from coupling high common-mode voltage into ground or reference paths. As confirmed in Table 6 and Table 7 of the AD8418A datasheet, this layout enables conditional fault tolerance-allowing the AD8418AWHRZ to maintain safe operation or fail gracefully under specific single-point PCB defects.

How does AD8418AWHRZ handle PWM switching noise?

AD8418AWHRZ integrates on-chip EMI filters and patented circuitry that maintains accuracy under PWM common-mode transients up to 1 V/ns. This is validated in the datasheet's Theory of Operation section and Figure 19–20 (common-mode step response), ensuring stable output even when placed adjacent to gate drivers or half-bridge switches. The feature is inherent to the AD8418AWHRZ silicon design and requires no external components.