Analog Devices Inc. AD7899ARZ-1

Overview

AD7899ARZ-1 from Analog Devices is a 14-bit, 400 kSPS successive-approximation ADC with integrated track/hold, 2.5 V reference, and high-speed parallel interface. It operates from a single 5 V supply, supports ±10 V and ±5 V bipolar input ranges, delivers 78 dB SNR at 100 kHz input, and features 2.2 µs conversion time for industrial data acquisition systems.

For engineers reviewing the AD7899ARZ-1 datasheet, AD7899ARZ-1 pinout, AD7899ARZ-1 application, or AD7899ARZ-1 equivalent, key selection criteria include bipolar input range compatibility, 14-bit DC accuracy (±2 LSB INL), low-power operation (80 mW typ), and support for both internal and external clocking in embedded measurement hardware.

Technical Context

The AD7899ARZ-1 implements a laser-trimmed internal clock oscillator enabling fixed 400 kSPS throughput or accepts external CLKIN up to 6.5 MHz for flexible timing control. Its track/hold amplifier achieves 0.3 µs acquisition time and 4.5 MHz –3 dB bandwidth, ensuring full-scale sine wave fidelity at Nyquist-limited frequencies.

Conversion initiation uses edge-triggered CONVST; BUSY/EOC signals end-of-conversion status, while parallel readout via 14-bit DB0–DB13 bus uses standard CS/RD handshaking. Input scaling circuitry supports ±10 V/±5 V ranges via resistor network (R1=4 kΩ, R2=16 kΩ, R3=16 kΩ, R4=8 kΩ), with two's complement output coding.

Key Specifications

Pinout & Package

AD7899ARZ-1 is housed in a 28-lead SOIC (Small Outline Integrated Circuit) package with standard 0.3-inch body width and gull-wing leads. Pin numbering follows top-view counterclockwise convention starting from the index notch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7899ARZ-1, AD7899BR-1 improves INL by 0.5 LSB at identical speed and power, while ADS8588SIPM trades parallel simplicity for channel count and sample rate-making AD7899ARZ-1 optimal for single-channel, low-latency, reference-integrated industrial DAQ.

Availability

AD7899ARZ-1 is available at Aetrix Electronics and suitable for industrial process monitoring, test & measurement equipment, and energy metering systems requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for AD7899ARZ-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 14-bit SAR ADCs with integrated references and robust industrial interfaces, designed specifically for precision data acquisition in harsh electromagnetic and thermal environments.

FAQ

What input voltage ranges does the AD7899ARZ-1 support?

The AD7899ARZ-1 supports ±10 V and ±5 V bipolar input ranges. Configuration is achieved by grounding VINB for ±10 V operation or tying VINA and VINB together for ±5 V operation. The device does not support unipolar 0 V to 5 V or ±2.5 V ranges-that functionality belongs to the AD7899-2 and AD7899-3 variants respectively. Input overvoltage protection allows up to ±18 V on the analog pins without damage.

Does the AD7899ARZ-1 require an external reference?

No, the AD7899ARZ-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 can be applied to VREF to override the internal source, but it is not mandatory. The internal reference has a typical temperature coefficient of 25 ppm/°C and 6 kΩ output impedance.

How is the AD7899ARZ-1 clocked, and what are the timing constraints?

The AD7899ARZ-1 uses either its internal laser-trimmed oscillator (default, ~6.5 MHz) or an external clock applied to CLKIN. Clock source selection is determined by CLKIN state on the rising edge of CONVST: high selects external clock, low selects internal. External clocks must have ≤60/40 duty cycle and start ≥100 ns after CONVST rising edge. Conversion time is fixed at 2.2 µs regardless of clock source.

What is the purpose of the OPGND pin on the AD7899ARZ-1?

The OPGND (Pin 14) is the dedicated ground return for all digital output drivers-including DB0–DB13 and BUSY/EOC-and must be connected to the system's analog ground plane. Separating output driver ground from main AGND/DGND reduces digital switching noise coupling into the analog signal path, preserving SNR and THD performance. It is not interchangeable with other ground pins.

Can the AD7899ARZ-1 interface directly with a 3 V microcontroller?

Yes, the AD7899ARZ-1 supports 3 V logic interfacing via the VDRIVE pin (Pin 15), which supplies voltage to all digital inputs and outputs. When VDRIVE is set to 3 V ±10%, the RD, CS, CONVST, and STBY inputs accept 3 V logic levels, and DB0–DB13 outputs drive to 3 V-compatible VOH/VOL thresholds. No level-shifting circuitry is required, simplifying connection to ARM Cortex-M or similar low-voltage MCUs.