Analog Devices Inc. AD7899ARS-1

Overview

AD7899ARS-1 from Analog Devices is a 14-bit, 400 kSPS successive-approximation ADC operating from a single 5 V supply, featuring an integrated 2.5 V reference, track/hold amplifier, and high-speed parallel interface. It supports ±5 V and ±10 V bipolar input ranges, delivers 78 dB SNR at 100 kHz input, and is used in precision data acquisition systems for industrial process control and automated test equipment.

For engineers reviewing the AD7899ARS-1 datasheet, AD7899ARS-1 pinout, AD7899ARS-1 application, or AD7899ARS-1 equivalent, key selection criteria include its 2.2 µs conversion time, ±2 LSB INL over –40°C to +85°C, 0.3 µs track/hold acquisition, 3 V/5 V digital interface compatibility via VDRIVE, and SSOP-28 package suitability for space-constrained PCB layouts.

Technical Context

The AD7899ARS-1 implements a laser-trimmed internal clock oscillator (2.2 µs conversion) or accepts external CLKIN up to 6.5 MHz for precise timing control. Its dual-mode BUSY/EOC output signals conversion status based on CONVST edge timing, enabling synchronous multi-channel sampling when coordinated across multiple devices.

Input scaling uses resistor networks to support configurable bipolar ranges (±5 V, ±10 V), with overvoltage protection allowing analog inputs up to ±18 V without damage. The 14-bit two's complement output is latched onto a 14-bit parallel bus (DB0–DB13), controlled by CS and RD with zero setup/hold requirements under VDRIVE = 5 V.

Key Specifications

Pinout & Package

AD7899ARS-1 is housed in a 28-lead Shrink Small Outline Package (SSOP, RS-28), 5.6 mm × 13.1 mm body, 0.65 mm pitch, with exposed pad not electrically connected. Pin 1 is marked by a beveled corner.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 14-bit SAR ADC applications.

Compared with AD7899AR-1, AD7899ARS-1 offers identical performance in a smaller SSOP package for higher-density layouts, while ADS8505IPW trades speed and interface simplicity for increased resolution and flexibility in reference and digital interface design.

Availability

AD7899ARS-1 is available at Aetrix Electronics and suitable for industrial process monitoring, motor drive feedback, and power quality analyzers requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for AD7899ARS-1 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, serving industrial, automotive, communications, and healthcare markets since 1965.

The AD7899 product line delivers high-speed, low-power, single-supply SAR ADCs with integrated references and flexible digital interfaces for precision data acquisition in harsh environments.

FAQ

What input voltage ranges does the AD7899ARS-1 support?

The AD7899ARS-1 supports ±5 V and ±10 V bipolar input ranges. Configuration is achieved by tying VINB to AGND for ±10 V operation or connecting VINA and VINB together for ±5 V operation, as defined in the Analog Devices AD7899 datasheet Rev. A, page 8. This matches the AD7899-1 variant specification and is confirmed in the Ordering Guide table on page 5.

Does the AD7899ARS-1 include an internal voltage reference?

Yes, the AD7899ARS-1 integrates a 2.5 V ±20 mV internal reference accessible via the VREF pin. It can be used directly with a 0.1 µF decoupling capacitor to AGND, or overdriven by an external 2.5 V ±5% reference such as the AD780 or REF43. Reference output impedance is 6 kΩ, and temperature coefficient is 25 ppm/°C typical, per datasheet pages 3 and 8.

What is the function of the VDRIVE pin on the AD7899ARS-1?

The VDRIVE pin supplies power to the digital I/O circuitry of the AD7899ARS-1 and determines logic voltage levels. It may be tied to VDD (5 V) for standard 5 V interface operation or to a 3 V ±10% supply to enable direct connection to 3 V microcontrollers and DSPs without level shifters, as specified in the Logic Inputs section (page 3) and PIN FUNCTION DESCRIPTIONS (page 6).

How does the BUSY/EOC pin operate on the AD7899ARS-1?

The BUSY/EOC pin serves a dual function: it asserts high at the rising edge of CONVST to indicate BUSY during conversion, then goes low to signal End-of-Conversion (EOC). Its exact behavior depends on the state of CONVST at conversion completion, as detailed in the Timing and Control section (pages 10–11). This allows flexible synchronization in both continuous and event-triggered acquisition modes.

Is the AD7899ARS-1 RoHS compliant and what is its operating temperature range?

Yes, the AD7899ARS-1 is RoHS compliant per Analog Devices' standard policy. Its specified operating temperature range is –40°C to +85°C (industrial grade), matching the "A" and "B" version designation in the Ordering Guide (page 5). Absolute maximum ratings confirm junction temperature limits up to 150°C, and thermal impedance is 95°C/W for the RS-28 package.