Analog Devices Inc. AD7621ACPZ

Overview

AD7621ACPZ from Analog Devices is a 16-bit, 3 MSPS, fully differential SAR analog-to-digital converter operating from a single 2.5 V supply. It features ±2 LSB INL, 2.048 V internal reference with ±7 ppm/°C drift, and supports parallel (16-/8-bit) or SPI/QSPI/MICROWIRE-compatible serial interfaces. It serves high-speed data acquisition in medical instruments and spectrum analysis systems.

For engineers reviewing the AD7621ACPZ datasheet, AD7621ACPZ pinout, AD7621ACPZ application, or AD7621ACPZ equivalent, key selection criteria include throughput mode flexibility (wideband warp/normal/impulse), differential input range (±VREF up to ±2.5 V), no missing codes guarantee, low power dissipation (65 mW @ 3 MSPS), and dual-interface support for FPGA or microprocessor integration.

Technical Context

The AD7621ACPZ employs charge redistribution SAR architecture with zero pipeline delay, enabling immediate data availability post-conversion. Its internal calibration circuitry corrects for capacitor DAC mismatch, ensuring ±2 LSB INL across −40°C to +85°C without external trimming.

It integrates dual-mode reference control (PDREF/PDBUF) supporting internal 2.048 V reference or external reference up to AVDD, with dedicated REFBUFIN and REFGND pins for precision buffering. Three configurable conversion modes-wideband warp (3 MSPS), normal (2 MSPS), and impulse (1.25 MSPS)-scale power linearly with throughput while maintaining full AC/DC accuracy specifications.

Key Specifications

Pinout & Package

AD7621ACPZ is housed in a 48-lead LFCSP (Lead Frame Chip Scale Package) with exposed paddle, optimized for thermal performance and high-density layout. Pin assignments follow standard ADC interface conventions with separate analog/digital grounds (AGND/DGND/OGND), dual supply domains (AVDD/DVDD/OVDD), and flexible mode-control inputs (WARP/IMPULSE/SER/PAR).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed SAR ADC applications.

Compared with AD7621ACPZ, AD7622BCPZ trades internal reference integration for tighter linearity and lower power at slightly reduced speed, while ADS8860IRGET sacrifices throughput and interface flexibility to achieve ultra-low power and minimal footprint - choice depends on whether system-level priority lies in speed, integration, or size.

Availability

AD7621ACPZ is available at Aetrix Electronics and suitable for medical imaging acquisition, high-speed spectrum analysis, and automated test equipment requiring stable component supply and long-term obsolescence management.

Supply support for AD7621ACPZ 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 AD76xx PulSAR® family - including AD7621ACPZ - was designed for high-speed, high-accuracy data acquisition in instrumentation, medical, and communications systems where SAR architecture delivers superior linearity without pipeline latency.

FAQ

What is the maximum sampling rate supported by the AD7621ACPZ?

The AD7621ACPZ supports a maximum throughput rate of 3 MSPS in wideband warp mode. This is achieved with a complete conversion cycle time of 333 ns and requires minimum inter-conversion timing constraints to maintain full DC and AC accuracy specifications. The AD7621ACPZ also operates at 2 MSPS in normal mode and 1.25 MSPS in impulse mode, allowing dynamic adjustment of speed versus power consumption based on system requirements.

Does the AD7621ACPZ include an internal voltage reference?

Yes, the AD7621ACPZ integrates a 2.048 V internal reference with ±7 ppm/°C temperature drift and 5 ms turn-on settling time when PDREF and PDBUF are driven low. This reference can be disabled via PDREF to accommodate external references up to AVDD, and the REFBUFIN pin allows use of the internal bandgap (1.2 V) to drive an external buffer for custom reference scaling - all confirmed in the AD7621ACPZ datasheet Rev. A, Table 2 and Pin Function Descriptions.

How does the AD7621ACPZ handle differential analog inputs?

The AD7621ACPZ accepts true differential analog inputs on IN+ and IN− pins with a full-scale range of ±VREF (up to ±2.5 V). Its fully differential architecture provides 55 dB CMRR at 100 kHz and supports input common-mode voltages from −0.1 V to AVDD when using the internal reference. The device requires matched PCB routing and local 10 μF + 100 nF decoupling at REFGND and AGND to maintain specified linearity and noise performance - details are validated in the Analog Inputs and Layout sections of the AD7621ACPZ datasheet.

Can the AD7621ACPZ operate with a 3.3 V digital interface supply?

Yes, the AD7621ACPZ supports OVDD supply voltages from 2.3 V to 3.6 V, making it compatible with 3.3 V logic families. Its digital outputs (D[15:0], BUSY, SYNC, SDOUT) are specified to drive OVDD − 0.3 V high and 0.4 V low under 500 μA load, and digital inputs accept VIH up to 5.25 V. This allows direct interfacing with 3.3 V FPGAs or microcontrollers without level shifters - confirmed in the Digital Inputs/Outputs and Power Supplies sections of the AD7621ACPZ datasheet Rev. A.

What package options are available for the AD7621ACPZ?

The AD7621ACPZ is exclusively offered in a 48-lead LFCSP (Lead Frame Chip Scale Package) with exposed thermal paddle, as indicated by the "ACPZ" suffix per Analog Devices' ordering guide. This package measures 7 mm × 7 mm × 0.85 mm and provides superior thermal resistance (θJC = 30°C/W) compared to the alternative 48-lead LQFP option (designated AD7621ASTZ). The LFCSP variant is optimized for high-density, thermally demanding applications such as portable medical equipment and compact ATE modules.