Analog Devices Inc. AD9251-40EBZ

Overview

AD9251-40EBZ from Analog Devices is a full-featured evaluation board designed to characterize the AD9251 12-bit, 40 MSPS analog-to-digital converter (ADC) in multiple configurations. It supports transformer-coupled or amplifier-based analog input paths, SPI-controlled setup, on-board 40 MHz Valpey Fisher oscillator (VFAC3-BHL-40MHz), and dual-channel CMOS output capture via HSC-ADC-EVALCZ FPGA platform.

For engineers reviewing the AD9251-40EBZ datasheet, AD9251-40EBZ pinout, AD9251-40EBZ application, or AD9251-40EBZ equivalent, this board enables rapid validation of AC performance (SNR, SFDR), clocking options (transformer/LVPECL/external), power supply configurations (LDO vs. ADP2114 switching), and interface modes (SPI/non-SPI, offset binary/twos complement).

Technical Context

The AD9251-40EBZ implements a dedicated signal chain for the AD9251 ADC, featuring dual 50 Ω differential analog inputs (Channel A/B), transformer-coupled clock input with T601 balun, and internal 1 V reference yielding 2 V p-p full-scale range. It supports both single-ended sine wave clock inputs (~2.8 V p-p) and differential LVPECL clocking via AD9517 (U701) when configured.

Power delivery includes default LDO regulation (6 V input → 1.8 V AVDD/DRVDD/DVDD) and optional ADP2114 switching regulator substitution for efficiency evaluation. Input drive supports up to ~150 MHz analog frequencies at 10 dBm (2 V p-p into 50 Ω), with jumper-selectable biasing (RBIAS = 10 kΩ), power-down (J205 Pins 1–2), and output enable (J205 Pins 3–4).

Key Specifications

Availability

AD9251-40EBZ is available at Aetrix Electronics and suitable for high-speed data acquisition, communications test equipment, and instrumentation applications requiring stable component supply, traceable sourcing, and long-term evaluation platform continuity.

Supply support for AD9251-40EBZ 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 (DSP) technologies, headquartered in Wilmington, MA.

The AD9251-40EBZ belongs to Analog Devices' high-speed ADC evaluation platform family, designed specifically to accelerate prototyping and performance validation of precision, low-power, dual-channel ADCs in RF, communications, and test & measurement systems.

FAQ

What is the primary function of the AD9251-40EBZ?

The AD9251-40EBZ is an evaluation board-not a semiconductor component-that provides complete hardware and software infrastructure to test and characterize the AD9251 12-bit, 40 MSPS dual-channel analog-to-digital converter. It includes configurable analog input paths, clocking options (on-board oscillator, external SMA, or AD9517), SPI interface, power regulation, and CMOS output routing to the HSC-ADC-EVALCZ FPGA capture platform. The AD9251-40EBZ enables engineers to validate dynamic performance metrics such as SNR, SFDR, and ENOB under real-world signal conditions before system integration.

Does the AD9251-40EBZ include the AD9251 IC?

Yes, the AD9251-40EBZ evaluation board is populated with the AD9251 ADC as the device under test (DUT). The board's schematic (Figure 18) confirms U101 as the AD9251, mounted in a 48-lead LFCSP package. All supporting circuitry-including input network (Figure 5), clock path (T601, Y601), power regulation (U102–U105 LDOs), and SPI interface (U301)-is designed around that specific IC. The AD9251-40EBZ cannot operate without the AD9251, and its performance specifications are intrinsically tied to that device's datasheet parameters.

What clock sources are supported by the AD9251-40EBZ?

The AD9251-40EBZ supports three clock source configurations: (1) On-board 40 MHz Valpey Fisher VFAC3-BHL-40MHz oscillator (enabled via J605), (2) External single-ended sine wave input via SMA connector J602 (50 Ω terminated, ~2.8 V p-p), and (3) Differential LVPECL clock from AD9517 (U701) when R607/R608 and R731/R732 are installed as 0 Ω resistors. All paths feed the AD9251's CLK+/CLK− inputs through low-jitter transformer coupling (T601), ensuring phase noise <1 ps rms jitter for optimal AC performance validation.

Can the AD9251-40EBZ be powered with external bench supplies?

Yes, the AD9251-40EBZ supports external bench power supplies in non-default configuration. To bypass the on-board LDOs, remove ferrite beads E101, E102, E114, E103, E105, and E107, then connect 1.8 V (1 A) supplies to P102 (DUT_AVDD/DRVDD) and P103 (DVDD), plus a separate 3.3 V (1 A) supply for 3V_CLK. Optional 5V_AMPVDD and 3V_AMPVDD rails (1 A each) are available for input amplifiers. This mode allows independent biasing of analog/digital domains and is documented in the UG-003 power supplies section (Page 3).

Which software tools are required to operate the AD9251-40EBZ?

Two primary software tools are required: VisualAnalog® for FFT-based AC performance analysis (SNR, SFDR, harmonic distortion) and SPI Controller for register-level configuration of the AD9251 (clock divide, data format, power-down, output enable). Both run on Windows (XP or later) and interface via USB to the HSC-ADC-EVALCZ FPGA capture board. Supporting documentation includes AN-905 (VisualAnalog), AN-878 (SPI Control), and AN-877 (SPI interfacing), all available at analog.com/fifo. The AD9251-40EBZ relies entirely on these tools for functional validation-no standalone operation is possible.