Analog Devices Inc. AD7863AR-3

Overview

AD7863AR-3 from Analog Devices is a dual-channel, simultaneous-sampling 14-bit analog-to-digital converter optimized for phase-critical signal acquisition in motor control and power quality monitoring. It delivers 175 kSPS throughput per channel, ±2.5 V input range, 5.2 μs conversion time, and integrated 2.5 V reference - enabling accurate capture of synchronized voltage/current waveforms in industrial inverters.

For engineers reviewing the AD7863AR-3 datasheet, AD7863AR-3 pinout, AD7863AR-3 application, or AD7863AR-3 equivalent, key selection criteria include simultaneous sampling capability, aperture delay matching (≤350 ps), bipolar ±2.5 V input compliance, parallel interface timing (t_CONV = 5.2 μs), and low-power operation (70 mW typical) in SOIC_W packaging.

Technical Context

The AD7863AR-3 integrates two independent successive approximation ADCs with matched track-and-hold amplifiers, enabling true simultaneous sampling across VA1/VA2 or VB1/VB2 pairs. Its internal 2.5 V reference and laser-trimmed oscillator eliminate external clock dependencies while maintaining <±8 LSB gain error match and ≤350 ps aperture delay mismatch between channels.

Operation relies on CONVST-triggered dual-track/hold hold mode initiation, BUSY-driven read synchronization, and A0-selectable channel pair routing. The 14-bit parallel interface uses standard CS/RD handshaking with 30 ns data access time and 5 ns bus relinquish time - supporting direct interfacing with ADSP-2100, TMS320C25, and MC68000 processors without glue logic.

Key Specifications

Pinout & Package

AD7863AR-3 is housed in a 28-lead SOIC_W (Wide-body Small Outline IC) package with 0.6 mm lead pitch and exposed pad thermal design. Pin layout supports compact routing of analog inputs (VA1, VA2, VB1, VB2), digital control (CONVST, CS, RD, A0), and 14-bit parallel data bus (DB0–DB13).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7863AR-3, AD7656ASTZ offers higher resolution at the cost of serial interface overhead and missing internal reference, while ADS8588HIPM provides greater channel count and speed but sacrifices input range optimization for ±2.5 V signals - making AD7863AR-3 the most balanced solution for cost-sensitive, phase-critical dual-channel acquisition.

Availability

AD7863AR-3 is available at Aetrix Electronics and suitable for motor control systems, power quality analyzers, and industrial data acquisition requiring stable component supply, long-term lifecycle support, and traceable sourcing from authorized channels.

Supply support for AD7863AR-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 was engineered specifically for high-fidelity, phase-coherent acquisition in real-time control and power monitoring systems - emphasizing simultaneous sampling, low aperture jitter, and robust industrial interface compatibility.

FAQ

What is the maximum analog input voltage the AD7863AR-3 can tolerate without damage?

The AD7863AR-3 supports ±7 V absolute maximum analog input voltage relative to AGND, as specified in its Absolute Maximum Ratings table. This overvoltage tolerance applies specifically to the AD7863-3 variant (including AD7863AR-3) and protects against transient surges in motor current sensing and grid voltage monitoring applications without requiring external clamping components. Exceeding ±7 V risks permanent damage to the input ESD structures.

Does the AD7863AR-3 require an external reference voltage, or does it have an internal one?

The AD7863AR-3 includes an internal 2.5 V reference accessible via the VREF pin, eliminating the need for an external reference in most applications. The internal reference has ±10 mV error at 25°C and a typical temperature coefficient of 25 ppm/°C. For higher accuracy, an external precision reference can be connected to VREF - but the AD7863AR-3's internal reference is fully functional and calibrated for ±2.5 V input range operation.

How does the AD7863AR-3 handle simultaneous sampling of two input pairs?

The AD7863AR-3 uses two matched track-and-hold amplifiers that enter hold mode simultaneously on the falling edge of CONVST, capturing VA1/VA2 or VB1/VB2 (selected by A0) at identical instants. This preserves phase relationships between signals - critical for vector control and power calculations. Aperture delay matching is guaranteed ≤350 ps, ensuring <0.1° phase error at 1 kHz, and both conversions complete in 5.2 μs with results available sequentially via the parallel bus.

Can the AD7863AR-3 interface directly with a microcontroller using standard parallel bus timing?

Yes, the AD7863AR-3 features a TTL-compatible 14-bit parallel interface with standard CS and RD control signals, supporting direct connection to microcontrollers like the MC68000, 80C196, and ADSP-2100 without glue logic. Timing parameters - including 30 ns data access time after RD falling edge and 5 ns bus relinquish time - comply with common microprocessor bus cycles. The BUSY signal provides ready indication, enabling polled or interrupt-driven read operations.

What is the power consumption profile of the AD7863AR-3 in active and power-down modes?

The AD7863AR-3 consumes 70 mW typical (16 mA at 5 V) in normal Mode 1 operation and drops to 105 μW maximum in power-down Mode 2. Power-down activates automatically after conversion completion and wakes before the next CONVST pulse, making it ideal for battery-powered data loggers. The 45 mW typical power dissipation (AD7863-2 variant) and 70 mW typical (AD7863-3 variant) are confirmed in the datasheet's Power Requirements table under VDD = 5.25 V conditions.