Analog Devices Inc. AD7899AR-1

Overview

AD7899AR-1 from Analog Devices is a 14-bit, 400 kSPS successive-approximation ADC with integrated track/hold, internal 2.5 V reference, and high-speed parallel interface. It operates from a single 5 V supply, supports ±5 V and ±10 V bipolar input ranges, delivers 78 dB SNR at 100 kHz input, and features 0.3 µs track/hold acquisition time. It is used in precision data acquisition systems for industrial process control and automated test equipment.

For engineers reviewing the AD7899AR-1 datasheet, AD7899AR-1 pinout, AD7899AR-1 application, or AD7899AR-1 equivalent, key selection criteria include bipolar input range support (±5 V/±10 V), two's complement output coding, internal clock operation at 2.2 µs conversion time, and compatibility with both 3 V and 5 V digital logic via VDRIVE pin.

Technical Context

The AD7899AR-1 implements a laser-trimmed internal oscillator for autonomous 400 kSPS operation or accepts external CLKIN up to 6.5 MHz for synchronized sampling. Its track/hold amplifier achieves full-scale settling within 0.3 µs and supports ±18 V overvoltage tolerance on analog inputs when configured for ±10 V range.

Conversion is initiated by CONVST rising edge, which places the track/hold into hold mode and triggers BUSY/EOC assertion. Data is latched onto DB13–DB0 after BUSY/EOC falls, using standard CS/RD strobes with 35 ns minimum read pulsewidth and 3–40 ns data access time depending on VDRIVE level.

Key Specifications

Pinout & Package

AD7899AR-1 is housed in a 28-lead SOIC (Small Outline Integrated Circuit) package with 0.6 mm lead pitch and standard JEDEC MS-012AC footprint. Pin 1 is marked by a beveled corner or dot; device orientation follows top-view pin numbering with pin 1 at top-left.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7899BR-1, the AD7899AR-1 trades 0.5 LSB INL for broader availability and lower cost; compared with AD7682BCPZ, it offers faster throughput and parallel interface simplicity at the expense of resolution and serial configurability.

Availability

AD7899AR-1 is available at Aetrix Electronics and suitable for industrial process monitoring, automated test equipment, motor drive current sensing, and power quality analyzers requiring stable component supply across extended temperature ranges.

Supply support for AD7899AR-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, Inc. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, founded in 1965 and headquartered in Wilmington, MA.

The AD7899 product line delivers high-speed, low-power, single-supply data converters for industrial and instrumentation applications where precision, robustness, and ease of integration are critical.

FAQ

What input voltage ranges does the AD7899AR-1 support?

The AD7899AR-1 supports ±5 V and ±10 V bipolar input ranges. Configuration is determined by external connections: for ±10 V, VINB is tied to AGND and signal applied to VINA; for ±5 V, VINA and VINB are shorted together. Input overvoltage tolerance reaches ±18 V in the ±10 V range, protecting against transient events without external clamping.

Does the AD7899AR-1 require an external reference?

No, the AD7899AR-1 includes an internal 2.5 V ±20 mV reference accessible via the VREF pin. A 0.1 µF decoupling capacitor to AGND is required for stable operation. An external 2.5 V ±5% reference may be connected to VREF to improve accuracy, as the internal reference is overdriven when an external source is present.

How is data read from the AD7899AR-1?

Data is read via a 14-bit parallel bus (DB13–DB0) using standard CS and RD strobes. After BUSY/EOC goes low, assert CS low, then pulse RD low for ≥35 ns. Valid data appears on DB[13:0] within 3–40 ns after RD falling edge, depending on VDRIVE voltage. Outputs are three-state and use two's complement coding.

Can the AD7899AR-1 interface with 3 V microcontrollers?

Yes - the VDRIVE pin allows independent supply of the digital I/O section. Tie VDRIVE to 3 V ±10% while maintaining VDD at 5 V. Logic thresholds automatically scale, supporting direct connection to 3 V MCUs without level-shifting circuitry. Input high/low thresholds become VDRIVE/2 ±0.4 V.

What is the power consumption of the AD7899AR-1 in standby mode?

In standby mode (STBY = low), the AD7899AR-1 draws 20 µA maximum, with typical current of 5 µA. This enables ultra-low-power operation during idle periods while retaining fast wake-up capability - conversion can resume within 5 µs after STBY returns high, minimizing latency in burst-sampling applications.