Texas Instruments ADS8471IRGZR

Overview

ADS8471IRGZR from Texas Instruments is a 16-bit, 1-MSPS pseudo-bipolar/unipolar SAR analog-to-digital converter with integrated 4.096-V reference, parallel 16-/8-bit interface, and zero-latency conversion. It delivers ±0.7 LSB max INL, 93 dB SNR, and operates from –40°C to +85°C in medical instrumentation and high-accuracy data acquisition systems.

For engineers reviewing the ADS8471IRGZR datasheet, ADS8471IRGZR pinout, ADS8471IRGZR application, or ADS8471IRGZR equivalent, key selection criteria include its 700 ns conversion time, internal reference buffer, 48-pin QFN package, and support for both unipolar (0 V to V_REF) and pseudo-bipolar input ranges without external op-amp circuitry.

Technical Context

The ADS8471IRGZR implements a capacitor-based successive approximation register (SAR) architecture with inherent sample-and-hold, enabling true zero-latency operation and eliminating external hold capacitors. Its internal clock generation ensures deterministic 700 ns conversion time independent of system clock jitter.

It supports dual digital supply domains (+VA = 4.75–5.25 V for analog core; +VBD = 2.7–5.25 V for parallel bus), enabling interfacing with 3.3-V or 5-V logic while maintaining full 16-bit performance. The BYTE pin enables flexible 8-bit bus read cycles by folding MSB bits onto DB[7:0], reducing FPGA/ASIC I/O count without sacrificing resolution integrity.

Key Specifications

Pinout & Package

ADS8471IRGZR is housed in a thermally enhanced 48-pin 7 mm × 7 mm QFN package (RGZ) with exposed thermal pad requiring PCB soldering for thermal and mechanical reliability. Pin numbering follows top-view orientation with pin 1 at top-left corner.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8472IRGZR and ADS8381IPWR, the ADS8471IRGZR uniquely balances 16-bit precision, 1-MSPS speed, integrated reference, and parallel interface in a single 48-pin QFN - minimizing total solution size and component count for mid-range industrial DAQ systems.

Availability

ADS8471IRGZR is available at Aetrix Electronics and suitable for medical instrumentation, optical networking, transducer interface, and high-accuracy data acquisition systems requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature grading.

Supply support for ADS8471IRGZR 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision data converters and industrial-grade signal chain solutions.

The ADS8471 belongs to TI's high-speed SAR ADC family designed for applications demanding zero-latency, high linearity, and integrated reference functionality - targeting medical imaging, test equipment, and industrial process control where deterministic timing and metrology-grade accuracy are essential.

FAQ

What is the maximum sampling rate supported by the ADS8471IRGZR?

The ADS8471IRGZR supports a maximum sampling rate of 1 MSPS, corresponding to a minimum conversion time of 700 ns. This throughput is sustained across the full industrial temperature range (–40°C to +85°C) and is enabled by its internally generated conversion clock and optimized SAR architecture. At this rate, the ADS8471IRGZR achieves 93 dB SNR and ±1 LSB INL, making it suitable for real-time signal capture in high-fidelity applications.

Does the ADS8471IRGZR require an external reference voltage?

No, the ADS8471IRGZR includes a precision 4.096-V internal reference with ±6 ppm/°C drift and 4.081–4.111 V output tolerance. When using the internal reference, REFOUT (pin 14) must be connected to REFIN (pin 13) with a 1-µF storage capacitor to ensure stable startup within 120 ms. An external reference is optional and supported over 3.0–4.2 V, but not required - reducing BOM count and layout complexity.

How does the BYTE pin function on the ADS8471IRGZR?

The BYTE pin (pin 3) configures the ADS8471IRGZR's parallel output bus mode: when LOW, it enables full 16-bit transfer on DB[15:0]; when HIGH, it activates 8-bit foldback mode where DB[7:0] carries the lower byte of the 16-bit result while DB[15:8] carries the upper byte - allowing 8-bit microcontrollers or FPGAs to read the full 16-bit word in two cycles without external multiplexing. This preserves resolution integrity while conserving I/O resources.

What is the recommended power supply decoupling for the ADS8471IRGZR?

For optimal performance, the ADS8471IRGZR requires separate decoupling for analog and digital supplies: each +VA pin (7,10,16,21,22,25) must have a local 0.1 µF ceramic capacitor to AGND; the +VBD pins (1,36) require identical 0.1 µF caps to BDGND; and the REFOUT–REFM node needs a 1-µF tantalum or ceramic capacitor. All capacitors must be placed within 2 mm of their respective pins, with short, wide traces to minimize inductance and preserve SNR and THD specifications.

Can the ADS8471IRGZR interface directly with a 3.3-V FPGA or microcontroller?

Yes, the ADS8471IRGZR supports direct interfacing with 3.3-V logic through its +VBD supply pin (pins 1,36), which accepts 2.7–5.25 V. When +VBD = 3.3 V, all digital outputs (DB[15:0], BUSY, RD) meet 3.3-V CMOS voltage levels (VOH ≥ 2.7 V, VOL ≤ 0.4 V), and inputs (CS, CONVST, BYTE) accept standard 3.3-V logic thresholds. No level-shifting circuitry is needed, simplifying interconnect and reducing propagation delay uncertainty.