Analog Devices Inc. EVAL-AD7679EDZ

Overview

EVAL-AD7679EDZ from Analog Devices is an evaluation board designed specifically for the AD7679 - a 18-bit, 571 kSPS PulSAR® successive approximation register (SAR) analog-to-digital converter with differential unipolar 0 to 5 V input range. It provides buffered parallel (18-bit) and serial interfaces, on-board precision reference (ADR435 or AD780), clock oscillator, signal conditioning op-amps, and analog/digital prototyping area. The board supports both stand-alone operation and integration with the EVAL-CED1Z capture system for data acquisition and performance analysis.

For engineers reviewing the EVAL-AD7679EDZ datasheet, EVAL-AD7679EDZ pinout, EVAL-AD7679EDZ application, or EVAL-AD7679EDZ equivalent, key selection considerations include its compatibility with AD7679's 48-lead LFCSP package, support for differential analog inputs up to 5 V_PP, configurable CNVST generation (internal/external), flexible interface modes (parallel/serial), and factory configuration for ±5 V bipolar input range (reconfigurable via solder pads S1–S7 for 0 to 5 V unipolar use with AD7679).

Technical Context

The EVAL-AD7679EDZ implements a 4-layer PCB layout optimized for high-resolution SAR ADC evaluation, with separate analog and digital ground planes joined under the ADC to minimize noise coupling. It uses a gate array (U10) to generate conversion control signals including CNVST, manage BUSY timing, and buffer 18-bit parallel output (BD[−2:15]) on a 40-pin IDC connector (P2) and 96-pin DIN interface (P3).

Analog signal conditioning includes dual op-amps (U6/U7) configured as unity-gain buffers at factory default, supporting selectable input ranges (0 to 5 V unipolar or ±5 V bipolar) via jumper and solder-pad configuration (JP1–JP22, S1–S7). Reference circuitry supports ADR435 (2.5 V), AD780 (2.5 V), or external sources, with optional buffering (JP20) and supply selection (JP4, JP7, JP8).

Key Specifications

Availability

EVAL-AD7679EDZ is available at Aetrix Electronics and suitable for high-precision data acquisition systems, industrial instrumentation, automated test equipment, and medical imaging subsystems requiring stable component supply and validated ADC evaluation infrastructure.

Supply support for EVAL-AD7679EDZ 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 Norwood, MA.

The EVAL-AD7679EDZ belongs to Analog Devices' PulSAR® evaluation platform family, engineered to accelerate development and validation of high-speed, high-accuracy SAR ADCs used in precision measurement and real-time signal capture applications.

FAQ

What is the primary function of the EVAL-AD7679EDZ?

The EVAL-AD7679EDZ is an evaluation board purpose-built for the AD7679 18-bit, 571 kSPS PulSAR® SAR ADC. It enables full characterization of the AD7679's dynamic performance (SNR, SINAD, THD, SFDR) and DC accuracy (transition noise, INL/DNL) using on-board signal conditioning, reference, clocking, and PC-based software. It is not a production-ready module but a design validation tool for engineers evaluating the AD7679 in system-level integration.

Does the EVAL-AD7679EDZ support the AD7679's native 0 to 5 V differential input range?

Yes - although the EVAL-AD76XXEDZ board is factory configured for ±5 V bipolar input (to support AD7663/AD7665/AD7671), it is fully reconfigurable for the AD7679's 0 to 5 V differential unipolar range. This requires modifying solder pads S1–S7 per the schematics and datasheet guidance, and setting JP1/JP2 to BUFF mode with appropriate amplifier supply selections (JP3, JP7, JP8) to match the 0 to 5 V signal swing.

Can the EVAL-AD7679EDZ operate without the EVAL-CED1Z capture board?

Yes - the EVAL-AD7679EDZ supports stand-alone operation using its on-board gate array (U10) to generate CNVST, manage BUSY timing, and drive buffered 18-bit parallel output (BD[−2:15]) on P2. In this mode, configuration switches S16 and S35 control interface behavior (e.g., word/byte mode, binary vs. 2's complement, read timing), and no USB host or CED software is required for basic conversion and data capture.

Which reference components are installed on the EVAL-AD7679EDZ for use with the AD7679?

The EVAL-AD7679EDZ includes either the ADR435 (2.5 V precision reference) or AD780 (2.5 V bandgap reference), selected via JP4 (REFS jumper). Both are supported by reference buffers (U2, U3) and configurable power supplies (JP7, JP20). For AD7679's 0 to 5 V input range, the on-board 2.5 V reference is used with internal gain scaling; no external reference is required unless higher accuracy or different voltage levels are needed.

How is analog input signal integrity maintained on the EVAL-AD7679EDZ?

Analog input integrity is ensured through a dedicated low-noise signal path: SMB connectors (J1/J2) feed into dual op-amp buffers (U6/U7) with selectable gain and supply rails (via JP1–JP3, JP7–JP8), followed by impedance-matched routing to the AD7679. The board uses split analog/digital ground planes joined only beneath the ADC, local decoupling (C26/C41), and shielded layout (Figure 14) to suppress noise coupling - critical for achieving the AD7679's specified 100.5 dB SNR and 110 dB SFDR.