Analog Devices Inc. AD8231TCPZ-EP-R7

Overview

AD8231TCPZ-EP-R7 from Analog Devices is a zero-drift, digitally programmable instrumentation amplifier with integrated uncommitted op amp, operating from −55°C to +125°C, offering gains of 1–128, 50 nV/°C max input offset drift, and rail-to-rail output. It serves as the front-end signal conditioner in precision sensor interfaces for aerospace data acquisition systems.

For engineers reviewing the AD8231TCPZ-EP-R7 datasheet, AD8231TCPZ-EP-R7 pinout, AD8231TCPZ-EP-R7 application, or AD8231TCPZ-EP-R7 equivalent, key selection criteria include military-temperature gain stability (10 ppm/°C for G = 1–32), shutdown current ≤1 µA, dual-amplifier architecture, and LFCSP-16 package compatibility with high-density PCB layouts.

Technical Context

The AD8231TCPZ-EP-R7 implements an auto-zero input stage for ultra-low drift and integrates two independent amplifiers: a digitally programmable instrumentation amplifier (IN-AMP) with eight discrete gain settings and a rail-to-rail op amp (OP AMP) sharing the same zero-drift architecture. Both amplifiers feature matched input bias current (≤500 pA typ) and temperature-stable CMRR (110 dB at G ≥ 32).

Digital gain control uses three logic inputs (A0–A2) with chip select (CS) enabling SPI-compatible configuration; shutdown (SDN) reduces quiescent current to ≤1 µA while placing both outputs in high-impedance state for multiplexed sensor arrays. The REF pin establishes output reference level with 28 kΩ input impedance.

Key Specifications

Pinout & Package

The AD8231TCPZ-EP-R7 is housed in a 4 mm × 4 mm, 16-lead Lead Frame Chip Scale Package (LFCSP, CP-16-17) with exposed thermal pad. The package supports soldering the EPAD to −VS or leaving it floating per layout requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD8421ARMZ and INA163UA, the AD8231TCPZ-EP-R7 uniquely combines military-temperature programmable gain, dual zero-drift amplifiers, and sub-µA shutdown-enabling compact, low-power, multi-sensor telemetry systems where gain agility and thermal robustness are non-negotiable.

Availability

AD8231TCPZ-EP-R7 is available at Aetrix Electronics and suitable for aerospace flight data recorders, downhole oil & gas sensors, and industrial motor control systems requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD8231TCPZ-EP-R7 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.

The AD8231-EP product line delivers enhanced reliability and extended temperature operation for defense, aerospace, and industrial applications where precision, longevity, and environmental resilience are critical.

FAQ

What is the maximum gain error specification for AD8231TCPZ-EP-R7 at G = 1?

The AD8231TCPZ-EP-R7 has a maximum gain error of 0.05% at G = 1, measured at 25°C with VS = 5 V and RL = 10 kΩ. This tight tolerance eliminates the need for system-level gain calibration in high-accuracy sensor interfaces, directly supporting compliance with MIL-STD-810H environmental test requirements for deployed AD8231TCPZ-EP-R7 units.

Can AD8231TCPZ-EP-R7 operate from a single 3.3 V supply?

Yes, the AD8231TCPZ-EP-R7 supports single-supply operation from 3 V to 6 V, including standard 3.3 V rails. At VS = 3.3 V, the input common-mode range extends from 0.05 V to 2.95 V and output swings from 60 mV to 2.94 V (RL = 10 kΩ), enabling direct interfacing with 3.3 V ADCs without level-shifting circuitry in the AD8231TCPZ-EP-R7 signal chain.

How does the shutdown function affect both amplifiers in AD8231TCPZ-EP-R7?

Asserting SDN low places both the instrumentation amplifier (OUTA) and the uncommitted op amp (OUTB) into high-impedance state while reducing total quiescent current to ≤1 µA. This allows multiplexing multiple AD8231TCPZ-EP-R7 devices onto a shared ADC input without external analog switches-critical for scalable sensor array architectures using the AD8231TCPZ-EP-R7.

Is the exposed thermal pad of AD8231TCPZ-EP-R7 required to be connected?

No, the exposed pad (EPAD) of the AD8231TCPZ-EP-R7 may be left floating or connected to −VS per PCB layout constraints. When soldered to −VS, θJA drops from 96°C/W to 54°C/W (JEDEC 4-layer board), improving thermal performance in sustained high-output-current operation-but floating is acceptable for low-duty-cycle applications where junction temperature remains below 105°C.

What is the minimum recommended reference voltage drive capability for the REF pin of AD8231TCPZ-EP-R7?

The REF pin of AD8231TCPZ-EP-R7 has 28 kΩ input impedance and must be driven by a low-impedance source (≤10 Ω) to prevent gain and offset errors. A dedicated op amp buffer or precision DAC output with <1 Ω source impedance is recommended; failure to meet this requirement degrades CMRR and introduces up to 10 µV of additional offset in the AD8231TCPZ-EP-R7 output path.