Analog Devices Inc. AD7658BSTZ-REEL

Overview

AD7658BSTZ-REEL from Analog Devices is a 12-bit, 6-channel simultaneous-sampling SAR ADC with true bipolar ±4×VREF (±10 V) and ±2×VREF (±5 V) input ranges, 250 kSPS throughput, on-chip 2.5 V reference, and parallel/serial/daisy-chain interface - used in multi-axis positioning systems requiring synchronized voltage acquisition across six channels.

For engineers reviewing the AD7658BSTZ-REEL datasheet, AD7658BSTZ-REEL pinout, AD7658BSTZ-REEL application, or AD7658BSTZ-REEL equivalent, key selection criteria include simultaneous sampling capability, bipolar input support, 12-bit resolution with ±1 LSB INL, 73 dB SINAD at 50 kHz, and 64-lead LQFP packaging with AGND/DGND separation for noise-sensitive industrial data acquisition.

Technical Context

The AD7658BSTZ-REEL integrates six independent 12-bit SAR ADCs on a single iCMOS die, enabling true simultaneous sampling via three dedicated CONVST pins (A/B/C), each controlling two ADCs. Its track-and-hold supports 12 MHz full-power bandwidth and achieves 4 ns max aperture delay matching between channels.

It features dual-mode interface control: parallel mode for high-speed microprocessor interfacing (with BUSY, RD, WR, CS), and SPI-/QSPI-/MICROWIRE-compatible serial mode with daisy-chain capability. Reference operation is flexible - internal 2.5 V ±0.1% output or external 2.5–3.0 V input - with 6 ppm/°C tempco and 150 ppm long-term stability.

Key Specifications

Pinout & Package

AD7658BSTZ-REEL is housed in a 64-lead LQFP (10 mm × 10 mm, 0.5 mm pitch) with exposed pad for thermal enhancement. Pin layout separates analog (AGND, AVCC, V1–V6, REFCAPx) and digital (DGND, DVCC, VDRIVE, DB0–DB15, CONVSTx) domains to minimize coupling.

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7656BSTZ-REEL and AD7657BSTZ-REEL, the AD7658BSTZ-REEL provides lowest-cost entry into simultaneous 6-channel acquisition with verified 12-bit performance, reduced BOM count via integrated reference, and identical pinout/package - enabling scalable platform design across precision tiers.

Availability

AD7658BSTZ-REEL is available at Aetrix Electronics and suitable for power line monitoring, multi-axis positioning systems, industrial instrumentation, and condition monitoring applications requiring stable component supply, long-lifecycle assurance, and RoHS-compliant packaging.

Supply support for AD7658BSTZ-REEL 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 AD7656/AD7657/AD7658 family was engineered for industrial data acquisition where simultaneous sampling, bipolar input handling, and system-level integration reduce component count - targeting motor control, power analytics, and automated test equipment.

FAQ

What is the maximum sampling rate of the AD7658BSTZ-REEL?

The AD7658BSTZ-REEL achieves a maximum throughput rate of 250 kSPS per channel in parallel interface mode. This rate is sustained across all six channels simultaneously, enabled by independent track-and-hold circuits and an internal oscillator that controls conversion timing without external clock dependency. The 3.1 µs conversion time and 550 ns acquisition window are fixed parameters validated across −40°C to +85°C (B version) operation.

Does the AD7658BSTZ-REEL support true bipolar input ranges?

Yes, the AD7658BSTZ-REEL supports true bipolar analog inputs of ±10 V (±4 × VREF) and ±5 V (±2 × VREF), selectable via the RANGE pin or software control bits RNGA–RNGC. Input leakage remains ≤±1 µA across both ranges, and the input capacitance is 10 pF (±4×VREF) or 14 pF (±2×VREF) in track mode - enabling direct connection to industrial sensors without external level-shifting or attenuation networks.

Can the AD7658BSTZ-REEL operate without an external reference?

Yes, the AD7658BSTZ-REEL includes an on-chip 2.5 V reference with ±0.1% initial accuracy, 6 ppm/°C temperature coefficient, and 150 ppm long-term stability (1,000 hours). When REFEN/DIS = 1, the internal reference is enabled and appears at the REFIN/REFOUT pin. External reference operation (2.5–3.0 V) is supported but not required - reducing bill-of-materials count in cost-sensitive AD7658BSTZ-REEL implementations.

What package type and pin count does the AD7658BSTZ-REEL use?

The AD7658BSTZ-REEL is supplied in a 64-lead LQFP package (10 mm × 10 mm, 0.5 mm pitch) with exposed thermal pad. It shares identical mechanical dimensions and pinout with AD7656BSTZ-REEL and AD7657BSTZ-REEL - enabling drop-in replacement within the same footprint. Thermal resistance is θJA = 45°C/W (4-layer board), and the package is rated for reflow soldering at 260°C (Pb-free).

How does the AD7658BSTZ-REEL handle simultaneous sampling across six channels?

The AD7658BSTZ-REEL implements simultaneous sampling using three dedicated CONVST inputs (A, B, C), each triggering two ADCs: CONVST A → V1/V2, CONVST B → V3/V4, CONVST C → V5/V6. Aperture delay matching is guaranteed ≤4 ns max between any two channels, preserving phase coherence for applications like three-phase current reconstruction. All six conversions complete within 3.1 µs, and results are available in parallel or serialized via DOUT A/B/C pins.