Analog Devices Inc. AD976AARZ

Overview

AD976AARZ from Analog Devices is a 16-bit, 200 kSPS BiCMOS successive-approximation analog-to-digital converter (ADC) with ±10 V bipolar input range, internal 2.5 V reference, on-chip clock, and high-speed parallel interface. It operates from a single 5 V supply, dissipates ≤100 mW, and delivers 83 dB signal-to-(noise + distortion) at 45 kHz input - suited for precision data acquisition in industrial instrumentation and automated test equipment.

For engineers reviewing the AD976AARZ datasheet, AD976AARZ pinout, AD976AARZ application, or AD976AARZ equivalent, this page provides verified technical context, package mapping, real-world timing behavior, functional alternatives, and supply-chain support for production-grade embedded ADC selection.

Technical Context

The AD976AARZ implements a switched-capacitor SAR architecture with laser-trimmed scaling resistors and factory-calibrated capacitor-array matching, eliminating external sample/hold circuitry. Its internal calibration coefficients are stored in thin-film resistors acting as ROM and applied dynamically during conversion to correct for capacitor mismatches and offset errors.

It supports two digital control modes: R/C-triggered conversion with CS held low (Figure 2), or dual-signal control using CS and R/C edges (Figure 3), enabling flexible integration with DSPs and microcontrollers. The BYTE pin allows full 16-bit parallel output or byte-swapped 8-bit reads on dedicated pin groups.

Key Specifications

Pinout & Package

AD976AARZ is housed in a 28-lead SOIC (Small Outline Integrated Circuit) package, 300 mil width, RoHS-compliant, with gull-wing leads and standard JEDEC MS-012AC footprint.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with ADS8860IDRCT and MAX11902ETX+, the AD976AARZ provides unique value in legacy industrial systems requiring ±10 V bipolar input, 5 V single-supply operation, and hardware-synchronized parallel readout - without redesigning timing logic or adding level-shifters.

Availability

AD976AARZ is available at Aetrix Electronics and suitable for industrial data acquisition, automated test equipment, and medical instrumentation requiring stable component supply across extended product lifecycles.

Supply support for AD976AARZ 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, founded in 1965 and headquartered in Wilmington, MA.

The AD976AARZ belongs to Analog Devices' precision SAR ADC product line, designed specifically for high-accuracy, moderate-speed data acquisition in industrial, instrumentation, and medical applications where ±10 V input compliance and single-supply simplicity are essential.

FAQ

What is the maximum sampling rate supported by the AD976AARZ?

The AD976AARZ supports a maximum throughput rate of 200 kSPS, corresponding to a minimum conversion cycle time of 5 µs. This is achieved using the internal clock and proper R/C and CS timing per Figure 2 in the datasheet. Performance remains within specification across the full –40°C to +85°C temperature range when operated with VANA = VDIG = 5 V ±5%.

Does the AD976AARZ require an external reference voltage?

No, the AD976AARZ includes a factory-trimmed internal 2.5 V reference (2.48 V to 2.52 V) that meets all AC and DC specifications. An external reference may be used only if tighter initial accuracy or lower temperature drift is required - in which case the external source must be 2.3 V to 2.7 V and capable of sinking 100 µA.

How does the BYTE pin affect data output on the AD976AARZ?

When BYTE is LOW, D15 (MSB) appears on Pin 6 and D0 (LSB) on Pin 22 for standard 16-bit parallel readout. When BYTE is HIGH, the top and bottom 8 bits are swapped: D15–D8 appear on Pins 15–22, and D7–D0 appear on Pins 6–13 - enabling byte-wise access for 8-bit microcontrollers without external multiplexing logic.

What are the grounding requirements for optimal performance of the AD976AARZ?

The AD976AARZ has three ground pins: AGND1 (reference ground), AGND2 (CAP buffer ground), and DGND (digital ground). All must be connected to a single-point analog ground plane near the device. AGND1 must serve as the reference for VIN and REF; separating AGND1 from AGND2 prevents reference noise coupling, while tying DGND to the same point minimizes digital switching noise injection into analog sections.

Can the AD976AARZ interface directly with a 3.3 V microcontroller?

No - the AD976AARZ digital outputs are 5 V CMOS-compatible (VOH ≥ 4 V, VOL ≤ 0.4 V) and inputs require VIH ≥ 2.0 V. Direct connection to 3.3 V logic risks violating input high threshold and may cause unreliable BUSY or CS detection. A level-shifter or 5 V-tolerant I/O buffer is required for safe interoperability with 3.3 V controllers.