Analog Devices Inc. AD8667ARZ

Overview

AD8667ARZ from Analog Devices is a dual, rail-to-rail output, precision CMOS operational amplifier optimized for low-noise, low-input-bias-current sensor signal conditioning. It delivers 175 µV max offset voltage, 23 nV/√Hz voltage noise, 300 fA input bias current, and operates from 5 V to 16 V single supply - enabling high-accuracy photodiode amplification and electrometer-grade transimpedance stages in portable medical and industrial instrumentation.

For engineers reviewing the AD8667ARZ datasheet, AD8667ARZ pinout, AD8667ARZ application, or AD8667ARZ equivalent, this page provides verified package mapping (8-lead SOIC_N), confirmed dual-amplifier topology, temperature-stable performance across −40°C to +125°C, and real-world design context for pH/ORP meters, DAC buffers, and low-power ADC drivers.

Technical Context

The AD8667ARZ integrates two independent precision op-amps sharing a common 5–16 V supply, each featuring DigiTrim®-calibrated offset (≤175 µV @ 5 V), rail-to-rail output swing (≤25 mV from rails @ 100 µA), and unity-gain stability with 520 kHz GBW. Its CMOS input stage enables femtoampere-level bias current critical for high-impedance node interfacing.

Designed for extended industrial operation, it maintains 1.5 µV/°C max offset drift and >76 dB CMRR over full temperature range while delivering <275 µA per amplifier supply current - balancing precision, power efficiency, and robustness in battery-powered and harsh-environment applications.

Key Specifications

Pinout & Package

AD8667ARZ is packaged in an 8-lead SOIC_N (R-8) with exposed pad (not connected). Pin 1 is marked by notch or beveled corner; pins are numbered counterclockwise. The exposed pad may be left unconnected or tied to V– for thermal enhancement.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual precision op-amp applications.

Compared with OP2177ARZ and ADA4077-2ARZ, AD8667ARZ offers the optimal balance of low power (275 µA), wide supply (5–16 V), and precision (175 µV VOS) for cost-sensitive industrial sensor nodes - trading minor offset/noise margins for significant energy savings and simplified power architecture.

Availability

AD8667ARZ is available at Aetrix Electronics and suitable for pH/ORP meters, photodiode amplifiers, and low-power ADC driver circuits requiring stable component supply across industrial temperature ranges and long production lifecycles.

Supply support for AD8667ARZ 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 Norwood, MA, with decades of expertise in precision amplification and data conversion.

The AD866x family was engineered specifically for high-impedance, low-noise sensor signal conditioning in portable and industrial instrumentation - emphasizing femtoampere bias, rail-to-rail output, and extended temperature reliability.

FAQ

What is the maximum supply voltage for AD8667ARZ?

The AD8667ARZ has an absolute maximum supply voltage rating of 18 V, but its specified operating range is 5 V to 16 V single supply (or ±2.5 V to ±8 V dual supply). Operating beyond 16 V risks violating electrical specifications and degrading long-term reliability, even if within absolute maximum limits. Always refer to Table 1 and Table 2 in the Rev. D datasheet for performance validation at specific voltages.

Does AD8667ARZ require external compensation for unity-gain stability?

No, AD8667ARZ is internally compensated and unity-gain stable - it drives capacitive loads up to 200 pF without oscillation, as confirmed in Figure 25 and Figure 28 of the datasheet. This eliminates the need for external compensation networks in standard buffer or transimpedance configurations, simplifying layout and reducing BOM count for the AD8667ARZ.

How is the exposed pad on AD8667ARZ configured?

The AD8667ARZ in SOIC_N (R-8) package does not feature an exposed pad - that configuration applies only to the LFCSP variant (e.g., AD8667ACPZ). The AD8667ARZ uses a standard SOIC body with no thermal pad; thermal management relies on PCB copper area connected to pins 4 (V–) and 8 (V+). Confusion arises from shared datasheet figures - always verify package option via ordering code: ARZ = SOIC_N.

Can AD8667ARZ drive heavy capacitive loads like LCD bias networks?

AD8667ARZ is not optimized for heavy capacitive loads (>1 nF); its phase margin drops below 45° beyond ~200 pF (per Figure 25/28). For LCD bias or large-capacitance filtering, use a dedicated buffer amplifier or add isolation resistance. The AD8667ARZ excels in precision, low-capacitance signal paths - such as photodiode TIA feedback or DAC output buffering - where stability and noise dominate.

Is AD8667ARZ pin-compatible with other dual op-amps in SOIC-8?

No, AD8667ARZ uses a non-standard pinout: OUT A/–IN A/+IN A/V–/+IN B/–IN B/OUT B/V+. It is not pin-compatible with industry-standard dual op-amps like LM358 or AD8602. Swapping requires PCB redesign. Always validate pin mapping using Figure 3 (8-Lead MSOP/SOIC) in the AD8667 datasheet - the AD8667ARZ follows the same pinout regardless of SOIC or MSOP packaging.