Analog Devices Inc. EVAL-AD7656CBZ

Overview

EVAL-AD7656CBZ from Analog Devices is a fully assembled, RoHS-compliant evaluation board for the AD7656 6-channel, 16-bit, 250 kSPS simultaneous-sampling SAR ADC. It supports ±10 V and ±5 V bipolar input ranges, features parallel/serial/daisy-chain interfaces, and includes on-board reference, power regulation, and signal conditioning circuitry for immediate lab validation of high-precision power monitoring and industrial control systems.

For engineers reviewing the EVAL-AD7656CBZ datasheet, EVAL-AD7656CBZ pinout, EVAL-AD7656CBZ application, or EVAL-AD7656CBZ equivalent, this board enables rapid functional verification of the AD7656's simultaneous sampling accuracy, channel-to-channel isolation (>100 dB), SNR (86.5 dB at 50 kHz), and iCMOS-based true bipolar input handling - critical for multi-axis positioning and power line monitoring designs requiring synchronized analog capture.

Technical Context

The EVAL-AD7656CBZ implements the full AD7656 signal chain: six independent 16-bit SAR ADCs with track-and-hold amplifiers supporting up to 12 MHz input bandwidth, internal 2.5 V reference with 6 ppm/°C tempco, and configurable ±4×VREF (±10 V) or ±2×VREF (±5 V) input ranges via RANGE pin or software control. It routes all 64 LQFP signals-including CONVST A/B/C, BUSY, RD/WR, DOUT A/B/C, and REF pins-to accessible headers and test points.

Power delivery uses discrete low-noise regulators for AVCC, DVCC, and VDRIVE (2.7–5.25 V), while analog and digital grounds are split and joined at a single-point star ground. The board supports both hardware (RANGE pin) and software (control register RNG bits) range selection, and provides jumper-selectable serial interface modes (SPI/QSPI/MICROWIRE/DSP-compatible) with daisy-chain capability.

Key Specifications

Availability

EVAL-AD7656CBZ is available at Aetrix Electronics and suitable for power line monitoring, instrumentation and control systems, and multi-axis positioning systems requiring stable component supply, pre-validated signal integrity, and traceable evaluation platform sourcing.

Supply support for EVAL-AD7656CBZ 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-AD7656CBZ belongs to Analog Devices' precision data acquisition evaluation platform family, designed to accelerate development of high-fidelity, multi-channel measurement systems in energy, industrial automation, and test equipment.

FAQ

What is the primary function of the EVAL-AD7656CBZ evaluation board?

The EVAL-AD7656CBZ is a dedicated evaluation platform for the AD7656 6-channel, 16-bit, 250 kSPS simultaneous-sampling ADC. It provides complete signal conditioning, regulated power supplies, reference circuitry, and interface headers to enable immediate functional testing and performance characterization of the AD7656 in real-world applications such as power quality monitoring and motion control. The board requires no additional hardware to begin evaluation of the EVAL-AD7656CBZ target device.

Does the EVAL-AD7656CBZ support both hardware and software configuration of input range?

Yes, the EVAL-AD7656CBZ supports dual-mode input range selection for the AD7656: hardware mode via the RANGE pin (jumper-selectable), and software mode via Bits RNGA–RNGC in the control register accessed over the parallel or serial interface. This allows flexible configuration during prototyping and system integration without hardware modification. Both methods configure the same ±4×VREF (±10 V) or ±2×VREF (±5 V) ranges supported by the underlying EVAL-AD7656CBZ design.

Can the EVAL-AD7656CBZ be used to evaluate daisy-chain operation of multiple AD7656 devices?

Yes, the EVAL-AD7656CBZ includes full serial interface routing with SCLK, CS, and SDATA lines exposed on headers, enabling direct connection to a host processor or FPGA for daisy-chain evaluation. The board's firmware-independent design allows users to implement multi-device daisy-chain configurations using the AD7656's native serial protocol - verified in the AD7656 datasheet Rev. D timing specifications (t16–t21) and functional block diagram. This capability is intrinsic to the EVAL-AD7656CBZ hardware architecture.

What power supply requirements must be met to operate the EVAL-AD7656CBZ?

The EVAL-AD7656CBZ requires a single +15 V DC input (±10%) applied to the J1 barrel connector. On-board regulators generate the precise voltages needed by the AD7656: AVCC = 5 V (±5%), DVCC = 5 V (±5%), VDRIVE = 3–5 V (user-selectable), and bipolar analog supplies VDD = +15 V and VSS = −15 V. All supplies meet AD7656 absolute maximum ratings and are decoupled per datasheet recommendations - ensuring stable operation of the EVAL-AD7656CBZ under full 250 kSPS throughput.

Is the EVAL-AD7656CBZ compatible with the AD7657 and AD7658 variants?

No, the EVAL-AD7656CBZ is specifically optimized for the AD7656 (16-bit resolution). While the AD7657 (14-bit) and AD7658 (12-bit) share the same 64-lead LQFP package and pinout, differences in internal reference buffering, noise performance, and DC accuracy specifications mean that evaluation results from the EVAL-AD7656CBZ cannot be directly extrapolated to those variants. Analog Devices provides separate evaluation boards - EVAL-AD7657CBZ and EVAL-AD7658CBZ - for accurate characterization of each respective device.