Analog Devices Inc. AD9649-20EBZ

Overview

AD9649-20EBZ from Analog Devices is a 14-bit, 20 MSPS analog-to-digital converter (ADC) operating from a single 1.8 V analog supply with differential 700 MHz input bandwidth, 74.3 dBFS SNR at 9.7 MHz, and on-chip voltage reference and sample-and-hold circuit-designed for low-power communications receivers and portable medical ultrasound front-ends.

For engineers reviewing the AD9649-20EBZ datasheet, AD9649-20EBZ pinout, AD9649-20EBZ application, or AD9649-20EBZ equivalent, key selection criteria include its 20 MSPS sampling rate, 1.8 V AVDD/1.8–3.3 V DRVDD dual-supply flexibility, SPI-configurable data format (offset binary/gray/twos complement), programmable clock divider (1/2/4), and LFCSP-32 RoHS-compliant package with exposed paddle grounding requirement.

Technical Context

The AD9649-20EBZ implements a multistage differential pipeline architecture with output error correction logic to guarantee 14-bit accuracy and no missing codes across −40°C to +85°C. Its sample-and-hold maintains ≤74.3 dBFS SNR up to 200 MHz input frequency and supports 2 V p-p differential analog input with 0.9 V common-mode voltage.

It features a standard 3-wire SPI interface for configuration of digital output timing alignment, DCO phase control, power-down modes, and built-in deterministic/pseudorandom test pattern generation. Clock input accepts CMOS/LVDS/LVPECL levels with internal 0.9 V common-mode bias and 0.2–3.6 V p-p differential range.

Key Specifications

Pinout & Package

The AD9649-20EBZ is housed in a 32-lead, 5 mm × 5 mm RoHS-compliant LFCSP with exposed paddle (EPAD) that must be soldered to the PCB's analog ground plane for thermal management, noise reduction, and mechanical integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD9649-20EBZ, AD9629-20EBZ trades 2 bits of resolution for lower cost and power, while AD9609-20EBZ further reduces resolution and SFDR-making AD9649-20EBZ the sole option among these three for applications demanding ≥74 dBFS SNR and ≥97 dBc SFDR at 20 MSPS.

Availability

AD9649-20EBZ is available at Aetrix Electronics and suitable for communications receivers, portable medical imaging systems, and handheld test equipment requiring stable component supply, long-term obsolescence management, and traceable sourcing for FDA-regulated designs.

Supply support for AD9649-20EBZ 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 technologies, headquartered in Norwood, MA, with design centers worldwide and ISO 9001-certified manufacturing.

The AD9649 product line delivers high-resolution, low-power ADCs optimized for communications infrastructure, portable medical diagnostics, and test instrumentation-emphasizing signal fidelity, power efficiency, and ease of integration into space-constrained platforms.

FAQ

What is the maximum analog input frequency supported by the AD9649-20EBZ?

The AD9649-20EBZ supports analog input frequencies up to 200 MHz while maintaining 71.5 dBFS SNR and 80 dBc SFDR. Its 700 MHz analog input bandwidth ensures minimal amplitude/phase roll-off for signals within this range, making it suitable for direct IF sampling in wireless receivers and ultrasound front-ends.

Does the AD9649-20EBZ require an external voltage reference?

No-the AD9649-20EBZ includes an on-chip 1.0 V voltage reference with ±12 mV tolerance over temperature. External reference is optional via the VREF pin; when used, the internal reference is disabled and SENSE pin configures reference mode per Table 10 of the datasheet.

How is the exposed paddle (EPAD) of the AD9649-20EBZ connected in PCB layout?

The EPAD must be soldered directly to the PCB's analog ground plane using multiple thermal vias. It serves as the sole ground connection for the die, critical for thermal dissipation, noise immunity, and mechanical reliability-failure to connect it results in degraded SNR, increased jitter, and potential functional failure.

Can the AD9649-20EBZ operate with a 3.3 V digital output supply?

Yes-DRVDD supports 1.8 V to 3.3 V, enabling direct interfacing with 3.3 V FPGA I/O banks. At 3.3 V DRVDD, digital outputs deliver VOH ≥3.25 V (at 0.5 mA) and VOL ≤0.2 V (at 1.6 mA), meeting standard CMOS logic thresholds without level-shifting circuitry.

What SPI configuration options are available for the AD9649-20EBZ data output format?

The AD9649-20EBZ supports offset binary, gray code, and twos complement formats via SPI Register 0x0C. Format selection is fully programmable and persists across power cycles when configured in non-volatile memory; default is offset binary after reset.