Analog Devices Inc. AD9221ARSZ

Overview

AD9221ARSZ from Analog Devices is a monolithic 12-bit analog-to-digital converter with 1.5 MSPS sampling rate, ±0.4 LSB typical integral nonlinearity, 70 dB SINAD, and on-chip sample-and-hold amplifier and voltage reference. It operates from a single 5 V analog supply and 2.7–5.25 V digital supply, delivering 59 mW typical power consumption for high-precision data acquisition in imaging and communications systems.

For engineers reviewing the AD9221ARSZ datasheet, AD9221ARSZ pinout, AD9221ARSZ application, or AD9221ARSZ equivalent, key selection criteria include its 28-lead SOIC package, straight binary output format, out-of-range (OTR) flag, differential/single-ended input flexibility, and guaranteed no missing codes over –40°C to +85°C.

Technical Context

The AD9221ARSZ implements a 4-stage differential pipelined ADC architecture with digital error correction logic, enabling true 12-bit accuracy and guaranteed no missing codes across temperature. Its sample-and-hold amplifier supports both single-ended and differential inputs with programmable common-mode level via CML and SENSE pins.

Internal voltage reference operates in 1 V or 2.5 V modes (±14 mV or ±35 mV tolerance), and the device uses rising-edge clock sampling with 3-clock-cycle pipeline latency. Aperture jitter is 4 ps rms, and full-power bandwidth is 25 MHz - optimized for direct IF sampling in communication receivers.

Key Specifications

Pinout & Package

AD9221ARSZ is housed in a 28-lead SOIC (Small Outline Integrated Circuit) package with standard JEDEC MS-013AC footprint, 1.27 mm pitch, and exposed pad not present. Thermal resistance θ_JA = 71.4°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 12-bit ADC applications.

Compared with AD9221AR, AD9221ARSZ adds RoHS-compliant matte-tin lead finish and enhanced moisture sensitivity level (MSL 3), while maintaining identical AC/DC performance and timing. Compared with ADS8320U, AD9221ARSZ delivers 15× higher throughput and integrated analog front-end functionality but trades off absolute DC accuracy for speed and simplicity.

Availability

AD9221ARSZ is available at Aetrix Electronics and suitable for medical imaging systems, industrial PLC analog input modules, communications baseband receivers, and test equipment requiring stable component supply and long-term obsolescence management.

Supply support for AD9221ARSZ 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 AD9221ARSZ belongs to the AD922x family of monolithic 12-bit pipelined ADCs designed for cost-sensitive, medium-speed data acquisition where linearity, low power, and integrated reference are critical - targeting imaging, instrumentation, and communications infrastructure.

FAQ

What is the maximum sampling rate supported by the AD9221ARSZ?

The AD9221ARSZ supports a maximum conversion rate of 1.5 MSPS, as specified in its datasheet under all operating conditions from –40°C to +85°C. This rate is fixed per device variant - the AD9221ARSZ is not field-programmable for higher rates like the AD9223 or AD9220. Exceeding 1.5 MSPS violates timing specifications and may cause data corruption or increased DNL.

Does the AD9221ARSZ require an external voltage reference?

No, the AD9221ARSZ includes a fully integrated, programmable voltage reference that operates in either 1 V or 2.5 V mode, selectable via the SENSE pin. External reference is optional and only needed when tighter initial tolerance (<±14 mV) or lower temperature drift is required than the internal reference provides.

How is the analog input configured for single-ended operation on the AD9221ARSZ?

For single-ended use, tie VINB to the CML pin (2.5 V) and drive the signal into VINA. The SENSE pin selects reference mode (and thus input span), while CML sets the common-mode bias. This configuration maintains optimal THD performance and avoids violating the input voltage range constraints relative to AVSS and AVDD.

What does the OTR (Out-of-Range) signal indicate on the AD9221ARSZ?

The OTR signal on the AD9221ARSZ is an active-high flag that asserts when the analog input exceeds the valid full-scale range - i.e., when |VINA – VINB| > VREF. Used with the MSB, it distinguishes between positive overflow (MSB = 1, OTR = 1) and negative overflow (MSB = 0, OTR = 1), enabling robust saturation handling in real-time signal processing firmware.

Is the AD9221ARSZ pin-compatible with other members of the AD922x family?

Yes, the AD9221ARSZ shares identical pinout, package (28-lead SOIC), and interface signals with the AD9223ARSZ and AD9220ARSZ. This allows drop-in replacement within the same footprint when system requirements change - for example, upgrading from 1.5 MSPS to 3 MSPS by swapping to AD9223ARSZ without PCB revision.