Analog Devices Inc. AD679JNZ

Overview

AD679JNZ from Analog Devices is a complete 14-bit monolithic sampling analog-to-digital converter (ADC) integrating sample-and-hold amplifier, internal 5 V reference, clock generator, and 8-bit bus interface. It delivers 128 kSPS throughput, 1 MHz full-power bandwidth, 10 MΩ input impedance, and supports both unipolar (0–10 V) and bipolar (±5 V) input ranges - used in precision data acquisition systems for industrial instrumentation and automated test equipment.

For engineers reviewing the AD679JNZ datasheet, AD679JNZ pinout, AD679JNZ application, or AD679JNZ equivalent, key selection criteria include its dual-read 14-bit output format, factory-trimmed dc accuracy (typical INL = 1 LSB), synchronous/asynchronous conversion control, and compatibility with microprocessor buses requiring minimal external support components.

Technical Context

The AD679JNZ employs a recursive subranging architecture with flash converter circuitry and error correction to achieve 14-bit resolution at 128 kSPS. Its on-chip sample-and-hold amplifier provides 1.5 µs input settling time and 150 ps aperture jitter, enabling accurate digitization of signals up to 500 kHz full-linear bandwidth.

It operates from +5 V (VDD), ±12 V (VCC/VEE) supplies, dissipating 560 mW typical. The J-grade version is specified for ac parameters (e.g., 76 dB S/N+D at –0.5 dB input) across 0°C to +70°C, with dc specifications provided as typicals - distinguishing it from K/B/T grades that guarantee full dc accuracy.

Key Specifications

Pinout & Package

AD679JNZ is packaged in a 28-lead plastic DIP (N-28) with through-hole mounting and 0.6-inch width. Pin functions are TTL/5 V CMOS compatible and support both synchronous and asynchronous operation via SYNC pin configuration.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution sampling ADC applications.

Compared with AD679JNZ, AD678JNZ trades resolution and integrated reference for speed and cost, while ADS8505IPFB offers higher resolution and simpler power but abandons parallel bus support - making AD679JNZ uniquely balanced for legacy industrial systems requiring 14-bit fidelity with minimal board redesign.

Availability

AD679JNZ is available at Aetrix Electronics and suitable for industrial data acquisition, automated test equipment, medical instrumentation, and communications signal analysis requiring stable component supply across extended product lifecycles.

Supply support for AD679JNZ 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 AD679 belongs to Analog Devices' precision data acquisition IC family, designed specifically for applications demanding high-resolution, high-speed sampling with minimal external components - targeting industrial, test, and medical instrumentation markets.

FAQ

What is the operating temperature range for the AD679JNZ?

The AD679JNZ is rated for commercial-grade operation from 0°C to +70°C. This J-grade variant guarantees ac performance (e.g., S/N+D, THD) across that full range, while dc parameters such as INL and gain error are specified as typical values - not guaranteed min/max limits - unlike the K/B/T grades which fully specify both ac and dc behavior.

Does the AD679JNZ require external calibration components?

The AD679JNZ is factory laser-trimmed for offset, gain, and linearity, so no external calibration is needed to achieve datasheet ac performance. For unipolar mode, only a single 50 Ω 1% resistor is required; bipolar mode needs two such resistors. If system-level accuracy tolerances allow, even those can be omitted - the AD679JNZ will still deliver its specified 76 dB S/N+D and 128 kSPS throughput.

How does the AD679JNZ handle 14-bit data output on an 8-bit bus?

The AD679JNZ uses a two-read sequence: first the high byte (DB7–DB0 containing bits D13–D6), then the low byte (same pins carrying D5–D0 padded with two zeros). HBE pin controls byte selection - LOW for high byte, HIGH for low byte. This left-justified format maintains compatibility with standard 8-bit microprocessor buses without requiring data alignment logic.

Can the AD679JNZ operate without the ±12 V analog supplies?

No - the AD679JNZ requires +12 V (VCC), –12 V (VEE), and +5 V (VDD) supplies to function. Its internal sample-and-hold amplifier and ADC core are designed for ±12 V rails; operation outside this range violates absolute maximum ratings and will cause permanent damage or undefined behavior. The datasheet explicitly cautions against using 15 V supplies.

Is the AD679JNZ pin-compatible with other members of the AD67x family?

Yes - the AD679JNZ shares identical pinout and footprint with the AD678 12-bit ADC, enabling drop-in upgrades in existing designs. This compatibility extends to all 28-pin DIP variants (e.g., AD678JNZ, AD679KN), allowing designers to increase resolution to 14 bits without PCB layout changes - provided the ±12 V supplies and timing constraints are met.