Analog Devices Inc. AD7863ARZ-3

Overview

AD7863ARZ-3 from Analog Devices is a dual-channel, simultaneous-sampling 14-bit analog-to-digital converter (ADC) with ±2.5 V input range, 5.2 μs conversion time, and single 5 V supply operation. It integrates two track-and-hold amplifiers, an internal 2.5 V reference, and a high-speed parallel interface - enabling phase-coherent acquisition in motor control, power quality monitoring, and digital oscilloscope front-ends.

For engineers reviewing the AD7863ARZ-3 datasheet, AD7863ARZ-3 pinout, AD7863ARZ-3 application, or AD7863ARZ-3 equivalent, key selection criteria include simultaneous dual-channel sampling capability, aperture delay matching ≤350 ps, channel-to-channel isolation of −86 dB, and compatibility with microprocessor-based data acquisition systems requiring ≤175 kSPS throughput.

Technical Context

The AD7863ARZ-3 implements two independent successive approximation register (SAR) ADCs sharing a common CONVST trigger and BUSY status signal, ensuring deterministic 5.2 μs conversion latency for both channels. Its dual-track/hold architecture preserves inter-channel phase relationships with aperture delay matching ≤350 ps and small-signal bandwidth of 7 MHz.

It operates in Mode 1 (high-speed sampling) with 175 kSPS per channel and supports ±2.5 V bipolar input scaling via internal signal conditioning. The 14-bit parallel interface uses TTL-compatible DB0–DB13 outputs with CS/RD handshaking and features 35 ns minimum CONVST pulse width and 30 ns data access time after RD falling edge.

Key Specifications

Pinout & Package

AD7863ARZ-3 is housed in a 28-lead SOIC_W (Wide-body Small Outline IC) package with 0.6 mm lead pitch and exposed thermal pad. Pin layout supports compact PCB routing for analog/digital partitioning and decoupling.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-channel simultaneous-sampling ADC applications.

Compared with AD7863ARZ-10 and AD7656ASTZ, the AD7863ARZ-3 offers optimal trade-off of ±2.5 V signal compatibility, 14-bit precision, and parallel bus simplicity for embedded microcontroller-based DAQ - avoiding level-shifting or protocol translation overhead while maintaining tight inter-channel timing.

Availability

AD7863ARZ-3 is available at Aetrix Electronics and suitable for motor control feedback, power quality monitoring, and digital oscilloscope front-ends requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for AD7863ARZ-3 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, headquartered in Norwood, MA.

The AD7863 product line delivers simultaneous-sampling dual-channel SAR ADCs optimized for real-time control and measurement systems where phase coherence, speed, and precision are critical - targeting industrial automation, test equipment, and energy infrastructure.

FAQ

What is the maximum sampling rate supported by the AD7863ARZ-3?

The AD7863ARZ-3 supports a maximum sustained sampling rate of 175 kSPS per channel in Mode 1 operation. This is enabled by its 5.2 μs conversion time and 400 ns quiet time requirement before the next CONVST pulse. At this rate, both channels deliver synchronized 14-bit samples without pipeline delay or interleaving artifacts.

Does the AD7863ARZ-3 require an external reference voltage?

No, the AD7863ARZ-3 includes an internal 2.5 V reference accessible via the VREF pin. When used, it delivers ±10 mV accuracy at 25°C and 25 ppm/°C temperature coefficient. External references may be applied to VREF only if tighter tolerance or lower drift is required - the internal reference is fully functional and recommended for most ±2.5 V range applications.

How does the A0 pin affect data readout sequence in the AD7863ARZ-3?

The A0 pin selects the analog channel pair prior to conversion: A0 = low activates VA1/VA2; A0 = high activates VB1/VB2. After conversion, the first RD pulse reads the result from the first input (VA1 or VB1), and the second RD pulse reads the second input (VA2 or VB2). This sequential readout is fixed per channel selection and requires no additional address decoding.

Can the AD7863ARZ-3 interface directly with a 3.3 V microcontroller?

No - the AD7863ARZ-3 uses TTL-compatible 5 V logic levels: VIH = 2.4 V min, VOL = 0.4 V max, and drives 200 μA high / 1.6 mA low. Direct connection to 3.3 V I/O requires level-shifting circuitry (e.g., dual-supply translators or resistive dividers on outputs) to avoid violating input voltage limits or degrading noise margins.

What is the purpose of the BUSY signal in the AD7863ARZ-3 timing sequence?

The BUSY signal is a high-active open-drain output that goes high on the falling edge of CONVST and remains high until conversion completes. It provides hardware-ready indication for the host processor, eliminating the need for polling or fixed delays. Data becomes valid 5.2 μs after CONVST fall, coinciding with BUSY going low - enabling deterministic, jitter-free read timing.