Analog Devices Inc. AD977AANZ

Overview

AD977AANZ 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 internal 2.5 V reference, high-speed serial interface, on-chip clock, 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 AD977AANZ datasheet, AD977AANZ pinout, AD977AANZ application, or AD977AANZ equivalent, key selection criteria include throughput rate (200 kSPS), INL (±3 LSB), power-down consumption (50 µW), and compatibility with external or internal reference configurations in high-accuracy measurement designs.

Technical Context

The AD977AANZ implements a factory-calibrated 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 external DATACLK synchronization via EXT/INT pin configuration.

It provides two data formats (Binary Two's Complement or Straight Binary) selected by SB/BTC, and enables daisy-chained readout of multiple devices using the TAG input with SYNC frame alignment - critical for multi-channel synchronized sampling without external timing coordination.

Key Specifications

Pinout & Package

AD977AANZ is housed in a 20-lead Skinny SOIC (SOIC_N) package with 0.3" body width and standard JEDEC MO-153 footprint. Pin functions are electrically validated per Analog Devices Rev. E datasheet Figure 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 AD977AANZ uniquely combines 200 kSPS throughput, hardware-selectable ±10 V/±5 V/±3.3 V bipolar operation, 5 V single-supply compatibility, and internal reference - making it irreplaceable in retrofitting legacy industrial DAQ systems without board redesign.

Availability

AD977AANZ is available at Aetrix Electronics and suitable for industrial process monitoring, automated test equipment, and medical instrumentation requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for AD977AANZ 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, serving industrial, automotive, communications, and healthcare markets since 1965.

The AD977AANZ belongs to Analog Devices' precision data acquisition product line, engineered for high-accuracy, low-power, single-supply 16-bit SAR ADC applications in harsh industrial environments.

FAQ

What is the maximum sampling rate supported by the AD977AANZ?

The AD977AANZ supports a maximum throughput rate of 200 kSPS, corresponding to a complete conversion cycle time of 5 µs. This is confirmed in Table 2 of the Rev. E datasheet under AD977A–SPECIFICATIONS. The AD977AANZ achieves this rate while maintaining full 16-bit resolution, ±3 LSB INL, and 83 dB SNR performance - distinguishing it from the slower AD977 variant (100 kSPS).

Does the AD977AANZ require an external reference voltage?

No, the AD977AANZ does not require an external reference voltage. It integrates a factory-trimmed 2.48–2.52 V internal reference, validated across temperature and supply variations. However, it also supports external reference inputs from 2.3 V to 2.7 V via the REF pin - enabling higher-precision or system-level reference sharing when needed. Both modes require a 2.2 µF tantalum capacitor on the CAP pin.

Which package type is used for the AD977AANZ?

The AD977AANZ uses a 20-lead Skinny SOIC (SOIC_N) package, as specified in the Ordering Guide and shown in Figure 3 of the Rev. E datasheet. This package has a 0.3" body width, gull-wing leads, and complies with JEDEC MO-153 standards - ensuring compatibility with standard surface-mount assembly processes and legacy industrial PCB footprints.

Can the AD977AANZ interface directly with a 3.3 V microcontroller?

The AD977AANZ digital interface operates at 5 V logic levels (VIH = 2.0–5.3 V, VOL = 0.4 V @ 1.6 mA), so direct connection to a 3.3 V microcontroller requires level translation on DATA, DATACLK, SYNC, and control lines. Its VDIG supply must remain at 4.75–5.25 V; applying 3.3 V to VDIG violates absolute maximum ratings and will damage the device. Level-shifting is mandatory for safe 3.3 V host interfacing.

How does the power-down mode affect data retention in the AD977AANZ?

In power-down mode (PWRD = HIGH), the AD977AANZ halts conversions and reduces supply current to 50 µW, but retains the most recent conversion result in its on-chip serial shift register. Upon exit from power-down, the stored 16-bit value remains accessible via the serial interface without requiring a new conversion - enabling low-power wake-up-and-read operation ideal for battery-powered data loggers. The AD977AANZ recovers full accuracy within 1 ms after PWRD deassertion.