Analog Devices Inc. AD872AJD

Overview

AD872AJD from Analog Devices is a monolithic 12-bit, 10 MSPS analog-to-digital converter with integrated track-and-hold amplifier and on-chip 2.5 V voltage reference, designed for high-fidelity imaging and undersampling applications requiring low noise (0.26 LSB RMS), no missing codes, and 68 dB SNR at 1 MHz input.

For engineers reviewing the AD872AJD datasheet, AD872AJD pinout, AD872AJD application, or AD872AJD equivalent, this page delivers verified specifications, ceramic DIP-28 package details, differential input interface guidance, and validated alternatives for precision data acquisition systems operating from 0°C to +70°C.

Technical Context

The AD872AJD employs a 4-stage pipelined multistage flash architecture with error correction logic, delivering 12-bit accuracy at full 10 MSPS throughput while guaranteeing no missing codes across its temperature range. Its differential input track-and-hold amplifier features 50 kΩ input resistance, 10 pF capacitance, and 35 MHz full-power bandwidth.

It uses a single rising-edge clock trigger with 100 ns minimum period, exhibits 3-clock-cycle pipeline latency, and supports both internal 2.5 V reference (±20 mV tolerance) and external reference inputs via dedicated REF IN/REF GND pins - enabling flexible dc accuracy and drift optimization in mixed-signal systems.

Key Specifications

Pinout & Package

AD872AJD is packaged in a 28-lead ceramic dual in-line package (DIP), rated for operation from 0°C to +70°C. Pin assignments are fully defined per Analog Devices Rev. A datasheet, with no NC pins in this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD9220AR and ADS8320U, the AD872AJD uniquely combines monolithic integration (T/H + reference), differential input, and 10 MSPS throughput - making it irreplaceable in space-constrained, noise-critical, high-dynamic-range sampling applications where latency and missing-code guarantees matter.

Availability

AD872AJD is available at Aetrix Electronics and suitable for medical ultrasound imaging, radar IF sampling, high-speed data acquisition, and digital oscilloscope front-ends requiring stable component supply and long-term obsolescence management.

Supply support for AD872AJD 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, founded in 1965 and headquartered in Wilmington, MA.

The AD872A product line was engineered specifically for high-fidelity, high-speed digitization in imaging, instrumentation, and communications - emphasizing low noise, guaranteed linearity, and monolithic integration to reduce system-level design risk.

FAQ

What is the operating temperature range for the AD872AJD?

The AD872AJD is specified for operation from 0°C to +70°C (J Grade). This range is validated per Analog Devices' Rev. A datasheet and applies to all DC and AC performance parameters including INL, SNR, and SFDR. The AD872AJD does not support extended temperature grades - for –55°C to +125°C operation, the AD872ASD variant must be selected. Thermal derating is not required within the J Grade envelope.

Does the AD872AJD require an external reference, or can it operate with its internal reference?

The AD872AJD can operate with its internal 2.5 V bandgap reference, accessible via REF OUT and applied to REF IN. When using the internal reference, REF OUT must be connected to REF IN, and REF GND must be tied to a low-impedance AGND point. The internal reference has ±20 mV tolerance and 30 ppm/°C drift (typ), sufficient for many imaging and acquisition applications. An external reference may be used for tighter dc accuracy.

What is the meaning of the OTR (Out-of-Range) signal on the AD872AJD?

The OTR signal on the AD872AJD is an active-HIGH digital output that asserts on the leading edge of code 0 or trailing edge of code 4096, indicating input signal saturation beyond the ±1 V full-scale range. It is synchronized to the conversion clock and can be used with the inverted MSB to distinguish low-side vs. high-side overflow. This hardware flag eliminates the need for software-based range checking in real-time control loops.

Is the AD872AJD pin-compatible with the AD872, and what are the key improvements?

Yes, the AD872AJD is pin-compatible with the AD872 per the datasheet: "The AD872A is pin compatible with the AD872, allowing the parts to be used interchangeably." Key improvements include reduced input-referred noise (0.26 LSB RMS vs. unspecified higher value in AD872), optimized T/H for faster settling (<40 ns), and enhanced SNR/SFDR performance - all achieved without layout changes or firmware updates.

How does the pipeline latency of the AD872AJD affect system timing?

The AD872AJD has a fixed 3-clock-cycle pipeline latency: a sample acquired on clock N appears at the output on clock N+3. This deterministic delay must be accounted for in closed-loop systems (e.g., offset calibration in video processors) and time-aligned multi-ADC architectures. Unlike successive-approximation ADCs, this latency does not vary with input level or temperature, enabling predictable timing budgeting in FPGA- or DSP-based controllers interfacing with the AD872AJD.