Analog Devices Inc. AD976ABRS

Overview

AD976ABRS from Analog Devices is a 16-bit, 200 kSPS BiCMOS successive-approximation analog-to-digital converter (ADC) with internal 2.5 V reference, ±10 V analog input range, and parallel 16-bit twos-complement output interface. It operates from a single 5 V supply, dissipates ≤100 mW, and targets precision data acquisition in industrial instrumentation and automated test equipment.

For engineers reviewing the AD976ABRS datasheet, AD976ABRS pinout, AD976ABRS application, or AD976ABRS equivalent, key selection criteria include its 200 kSPS throughput, ±3 LSB integral nonlinearity (B-grade), 85 dB signal-to-(noise + distortion), SSOP-28 package compatibility, and factory-calibrated DC/AC performance across –40°C to +85°C.

Technical Context

The AD976ABRS implements a switched-capacitor SAR architecture with on-chip laser-trimmed capacitor array calibration, eliminating external sample-and-hold circuitry. Its internal 2.5 V reference (±20 mV tolerance) and programmable BYTE control enable flexible 16-bit or byte-wise parallel data readout.

Conversion is initiated by R/C or CS falling edges, with BUSY signaling completion; aperture delay is fixed at 40 ns, and overvoltage recovery requires 150 ns after 2× full-scale transients. The device uses separate analog (AGND1/AGND2) and digital (DGND) grounds to maintain 90 dB SFDR and 85 dB S/(N+D) at 45 kHz input.

Key Specifications

Pinout & Package

AD976ABRS is housed in a 28-lead Shrink Small Outline Package (SSOP, RS-28), 5.6 mm × 13.6 mm body, 0.635 mm pitch, with exposed pad not electrically connected. Pin functions are validated per Analog Devices Rev. D datasheet Figure 6 and Pin Function Descriptions table.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD976ABRS, ADS8860IDRCT trades parallel simplicity for speed and power efficiency, while MAX11902ETX+ adds digital robustness but increases analog front-end complexity-neither offers identical pin-compatible replacement without interface or layout changes.

Availability

AD976ABRS is available at Aetrix Electronics and suitable for industrial process monitoring, automated test equipment, medical diagnostic signal acquisition, and energy metering reference calibration requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD976ABRS 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 AD976 family was designed as a complete, factory-calibrated 16-bit data acquisition solution for industrial and instrumentation applications demanding high DC accuracy, low power, and minimal external components.

FAQ

What is the guaranteed integral nonlinearity (INL) specification for AD976ABRS?

The AD976ABRS is rated as a B-grade device with guaranteed integral nonlinearity of ±2.0 LSB over the full –40°C to +85°C operating range, as confirmed in the AD976A ordering guide and Rev. D specifications table. This corresponds to <15 ppm linearity error relative to full-scale ±10 V input, enabling high-accuracy calibration without user trimming. The AD976ABRS maintains this specification with internal reference and 5 V supplies.

Does AD976ABRS require an external reference, or does it include an internal one?

The AD976ABRS includes a factory-trimmed internal 2.5 V reference (2.48 V to 2.52 V) that is fully functional and specified for all AC/DC performance parameters. An external reference (2.3 V to 2.7 V) may be applied at the REF pin to override the internal source, but it is not required. When using the internal reference, the CAP pin must be decoupled to AGND2 with a 2.2 µF tantalum capacitor to ensure stability.

What package type and footprint does AD976ABRS use?

The AD976ABRS uses a 28-lead Shrink Small Outline Package (SSOP) with designation RS-28, measuring 5.6 mm × 13.6 mm with 0.635 mm lead pitch. It is pin-compatible with other AD976xRS variants (e.g., AD976ARS, AD976CRS) and shares the same pinout as the SOIC (R-28) and PDIP (N-28B) versions, though physical dimensions differ. No exposed thermal pad is present.

How is data read from AD976ABRS - parallel or serial interface?

The AD976ABRS features a high-speed parallel 16-bit interface with binary twos-complement output format. Data is latched onto D0–D15 pins following BUSY going HIGH after conversion. The BYTE pin allows configuration for full-word (pins 6–13 and 15–22) or byte-swapped output. No serial interface is provided - communication is strictly parallel, compatible with microcontrollers and DSPs having 16-bit data buses.

What is the maximum sampling rate and corresponding acquisition time for AD976ABRS?

The AD976ABRS achieves a maximum throughput rate of 200 kSPS, with a total conversion time of 4.0 µs and acquisition time of 2.0 µs (per AD976A timing specs). This enables continuous sampling of input signals with full 16-bit accuracy at intervals as short as 5 µs. The device sustains this rate across its full operating temperature range when powered with 5 V ±5% on both VANA and VDIG rails.