Analog Devices Inc. AD7884AP

Overview

AD7884AP from Analog Devices is a 16-bit monolithic sampling analog-to-digital converter with internal sample-and-hold, 5.3 µs conversion time, ±5 V or ±3 V input ranges, and 166 kSPS throughput. It delivers 84 dB SNR and ±0.0075% FSR integral nonlinearity in industrial data acquisition systems requiring high-resolution DC and dynamic performance.

For engineers reviewing the AD7884AP datasheet, AD7884AP pinout, AD7884AP application, or AD7884AP equivalent, this page provides verified package mapping (44-lead PLCC), confirmed 16-bit parallel output architecture, validated timing parameters (t2 = 100 ns CONVST-to-BUSY delay), and real-world interface constraints including dual-supply operation (±5 V) and 3 V reference dependency.

Technical Context

The AD7884AP implements a two-pass flash ADC architecture: first pass captures 9 MSBs via a 9-bit flash converter and feeds them to an on-chip 16-bit DAC; second pass digitizes the residue error using the same 9-bit core. This enables 16-bit resolution at 166 kSPS while maintaining monotonicity and no missing codes.

It uses separate analog (AVDD/AVSS) and digital (VDD/VSS) supplies with dedicated AGNDS/AGNDF force-sense ground paths for the 9-bit ADC section, and supports bipolar input ranges via configurable ±5VINF/±5VINS or ±3VINF/±3VINS pins - all controlled by external op-amp buffering per Figure 6 of the datasheet.

Key Specifications

Pinout & Package

AD7884AP is packaged in a 44-lead Plastic Leaded Chip Carrier (PLCC), designated P-44A in the ordering guide. The package includes dedicated analog/digital supply and ground pins, dual reference sense/force inputs, and 16-bit parallel data outputs DB0–DB15.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit high-speed ADC applications.

Compared with AD7884AQ, AD7884AP offers better thermal performance in surface-mount systems; compared with AD7885AAP, it eliminates software byte-assembly overhead and delivers full 16-bit words in one read cycle - critical for real-time control loops.

Availability

AD7884AP is available at Aetrix Electronics and suitable for industrial control, medical instrumentation, and automatic test equipment requiring stable component supply across extended temperature ranges (–40°C to +85°C).

Supply support for AD7884AP 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, headquartered in Norwood, MA.

The AD7884 product line delivers monolithic 16-bit sampling ADCs optimized for precision industrial and instrumentation applications where speed, linearity, and dual-range flexibility are essential.

FAQ

What is the maximum sampling rate supported by the AD7884AP?

The AD7884AP supports a maximum throughput rate of 166 kSPS, achieved through overlapped acquisition and conversion phases. This value is guaranteed under specified conditions: VDD = +5 V ±5%, VSS = –5 V ±5%, VREF+S = 3 V, and operating temperature from –40°C to +85°C. The 5.3 µs conversion time and 2.5 µs acquisition time enable this sustained rate without dead time between samples.

Does the AD7884AP require an external clock source?

No, the AD7884AP does not require an external clock source. It contains an internal oscillator that controls the conversion timing sequence. This eliminates the need for external clock generation circuitry and simplifies system-level timing design, especially in noise-sensitive analog environments where clock distribution can introduce jitter or interference.

Can the AD7884AP operate with a single +5 V supply?

No, the AD7884AP cannot operate with a single +5 V supply. It requires dual supplies: +5 V (VDD, AVDD) and –5 V (VSS, AVSS), both regulated to ±5% tolerance. The analog input structure and internal DAC architecture depend on symmetric bipolar rails to support ±5 V or ±3 V input ranges. Attempting single-supply operation will result in functional failure or damage.

What is the purpose of the AGNDS and AGNDF pins on the AD7884AP?

The AGNDS (analog ground sense) and AGNDF (analog ground force) pins form a Kelvin connection for the 9-bit ADC section's ground return path. They must be driven by a low-offset, low-noise buffer amplifier (e.g., AD817) referenced to system AGND. Directly tying AGNDS and AGNDF together degrades integral nonlinearity and gain accuracy - the datasheet specifies this configuration causes measurable INL and bipolar zero error degradation.

How does the AD7884AP handle reference voltage noise sensitivity?

The AD7884AP requires a clean 3 V reference (VREF+S) with ≤35 µV rms noise in the 100 kHz band to avoid degrading its 120 µV rms internal noise floor. The AD780 reference IC, buffered by an AD845 or AD817 amplifier, is explicitly recommended in the datasheet. Reference noise directly modulates conversion gain and appears as code uncertainty - exceeding the 35 µV threshold reduces effective resolution below 16 bits.