Analog Devices Inc. AD977AARZ

Overview

AD977AARZ from Analog Devices is a 16-bit, 200 kSPS successive-approximation analog-to-digital converter (ADC) operating from a single 5 V supply. It features factory-calibrated linearity, on-chip 2.5 V reference, high-speed serial interface, and supports ±10 V, ±5 V, ±3.3 V bipolar and 0 V–10 V/0 V–5 V/0 V–4 V unipolar input ranges - deployed in precision industrial data acquisition and process control systems.

For engineers reviewing the AD977AARZ datasheet, AD977AARZ pinout, AD977AARZ application, or AD977AARZ equivalent, key selection considerations include throughput rate (200 kSPS), internal vs. external clock mode flexibility, power-down capability (50 µW), serial data format selection (two's complement or straight binary), and compatibility with 20-lead SOIC packaging for space-constrained embedded measurement nodes.

Technical Context

The AD977AARZ implements a switched-capacitor SAR architecture with integrated reference buffer and serial output register. Its conversion control relies on dual digital inputs (R/C and CS), supporting both internal clock generation and externally synchronized readout via DATACLK and SYNC signals.

It provides configurable analog input scaling through external resistor networks (R1IN/R2IN/R3IN), supports daisy-chained multi-device operation using the TAG pin, and includes error correction circuitry to mitigate bit decision errors during the first half of conversion cycles - ensuring robustness against noise and settling anomalies.

Key Specifications

Pinout & Package

AD977AARZ is packaged in a 20-lead narrow-body SOIC (SOIC_N) with 0.3" body width and standard 1.27 mm pitch. Pin functions are validated per Analog Devices Rev. E datasheet Figures 3 and Table 6.

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 AD977AARZ uniquely combines 200 kSPS throughput, ±10 V bipolar input, internal clock mode, and TAG-based daisy chaining - making it optimal for cost-sensitive, space-constrained industrial DAQ nodes requiring deterministic multi-channel synchronization without FPGA logic overhead.

Availability

AD977AARZ is available at Aetrix Electronics and suitable for industrial process monitoring, automated test equipment, and medical instrumentation requiring stable component supply, long-term lifecycle support, and traceable sourcing for certified production programs.

Supply support for AD977AARZ 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, serving industrial, automotive, communications, and healthcare markets.

The AD977AARZ belongs to Analog Devices' precision SAR ADC product line, designed specifically for high-accuracy, medium-speed data acquisition in harsh industrial environments where reliability, calibrated linearity, and flexible interfacing are critical.

FAQ

What is the maximum sampling rate supported by the AD977AARZ?

The AD977AARZ supports a maximum throughput rate of 200 kSPS, corresponding to a complete conversion cycle time of 5 µs. This specification applies across all grade versions (A/B/C) and is validated at –40°C to +85°C with 5 V supplies. The AD977AARZ achieves this rate using its factory-calibrated switched-capacitor SAR architecture and on-chip clock generation - distinct from the 100 kSPS AD977 variant.

Does the AD977AARZ require an external reference voltage?

No, the AD977AARZ does not require an external reference voltage. It integrates a 2.5 V ±2% internal reference (2.48 V–2.52 V) accessible at the REF pin, which can be used directly with proper 2.2 µF decoupling to AGND2. An external 2.3 V–2.7 V reference may optionally replace the internal one for higher accuracy or system-level reference sharing - but is not mandatory for basic operation of the AD977AARZ.

How is the AD977AARZ interfaced to a microcontroller?

The AD977AARZ interfaces to microcontrollers via a configurable high-speed serial interface. Using the EXT/INT pin, users select between internal clock mode (DATACLK output, self-timed) or external clock mode (DATACLK input, SYNC-aligned). Data is output MSB-first on the DATA pin, with format controlled by SB/BTC. R/C and CS pins manage conversion initiation and read enable - allowing simple GPIO or SPI peripheral integration without custom timing logic for the AD977AARZ.

What package type is used for the AD977AARZ?

The AD977AARZ is supplied in a 20-lead narrow-body SOIC (SOIC_N) package, also designated as "ARZ" in Analog Devices' ordering nomenclature. This package has a 0.3" body width, 1.27 mm lead pitch, and meets JEDEC MS-013 standards. It is distinct from the 28-lead SSOP option (AD977AARS) and the obsolete PDIP variant - confirming the AD977AARZ's physical form factor for PCB layout and thermal design.

Can multiple AD977AARZ devices be synchronized for simultaneous sampling?

Yes, multiple AD977AARZ devices can be synchronized using the TAG pin and external clock mode. When EXT/INT = HIGH, the TAG input level is inserted into the DATA stream after 16–17 DATACLK edges, enabling time-stamped daisy-chained reads. Combined with common R/C and CS control, this allows deterministic interleaved or parallel sampling across multiple AD977AARZ units - critical for phase-coherent multi-channel acquisition without external trigger distribution hardware.