Texas Instruments ADS8284IBRGCT

Overview

ADS8284IBRGCT from Texas Instruments is an 18-bit, 1-MSPS pseudo-bipolar differential SAR ADC with integrated on-chip ADC driver (OPA), 4-channel differential multiplexer, internal 4-V reference, and 18-/16-/8-bit parallel interface. It supports ±4-V input range with 2-V common-mode, delivers 98.4 dB SNR at 2 kHz, and operates across –40°C to +85°C in medical CT scanners and high-speed data acquisition systems.

For engineers reviewing the ADS8284IBRGCT datasheet, ADS8284IBRGCT pinout, ADS8284IBRGCT application, or ADS8284IBRGCT equivalent, this page provides verified specifications, validated pin functions, confirmed multiplexer timing behavior, and real-world design context for high-precision analog signal digitization in safety-critical embedded systems.

Technical Context

The ADS8284IBRGCT integrates a 4-channel differential multiplexer with auto/manual scan control (via AUTO, C3/C2/C1, MXCLK), followed by a matched OPA stage optimized for 50-Ω source impedance, then an 18-bit SAR ADC with zero-latency conversion. Its internal reference buffer (BUF-REF) and VCMO (REF/2) outputs enable bipolar signal level-shifting and common-mode setting without external components.

Timing is synchronized via CONVST (active-low convert start) and RD/CS/BYTE/BUS18_16 for parallel data readout; BUSY indicates conversion status. The device supports three bus widths (18/16/8-bit) and dual supply domains (+VA/AGND for analog, +VBD/BGND for digital, VCC/VEE for OPA), with independent power sequencing requirements.

Key Specifications

Pinout & Package

ADS8284IBRGCT is housed in a thermally enhanced 64-pin QFN package (9 mm × 9 mm) with exposed thermal pad. Pin functions are validated per TI SLAS628A datasheet Rev. April 2014, including dedicated analog/digital/power domains and multiplexer control logic.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8284IBRGCT, ADS8484IRGCT offers higher speed but demands more external circuitry, while ADS8382IPWR reduces integration and power at the expense of throughput and feature set - making ADS8284IBRGCT optimal for compact, multi-channel, high-fidelity SoC-style implementations.

Availability

ADS8284IBRGCT is available at Aetrix Electronics and suitable for medical imaging systems, automated test equipment, and high-speed data acquisition requiring stable component supply and long-term production continuity.

Supply support for ADS8284IBRGCT 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 signal chain solutions.

The ADS8284IBRGCT belongs to TI's high-performance SAR ADC product line, designed specifically for system-on-chip analog acquisition in medical, industrial, and test instrumentation where integration, accuracy, and timing determinism are critical.

FAQ

What is the meaning of "Not Recommended for New Designs" for ADS8284IBRGCT?

The "Not Recommended for New Designs" designation indicates that Texas Instruments no longer promotes ADS8284IBRGCT for newly initiated projects due to newer alternatives like ADS8484 or ADS868x families. However, ADS8284IBRGCT remains fully supported, in active production, and available through authorized distributors including Aetrix Electronics for legacy program continuity and existing design refreshes.

Does ADS8284IBRGCT require external decoupling capacitors, and where should they be placed?

Yes, ADS8284IBRGCT requires specific decoupling: 0.1 µF between REFIN and REFM (Pin 10–8/9), 1 µF between REFOUT and REFM (Pin 11–8/9), and 1 nF across INP–INM (Pins 25–27). Additional 0.1 µF capacitors are required on +VA, +VBD, VCC, and VEE supplies close to their respective pins to suppress high-frequency noise and ensure stable operation at 1 MSPS.

How does the multiplexer auto-scan mode work on ADS8284IBRGCT?

In auto-scan mode (AUTO = HIGH), the ADS8284IBRGCT cycles through channels CH0 to CHn (n = C3C2C1 binary value) on each rising edge of MXCLK. Channel count is programmable from 1 to 4; for example, C3=1, C2=0, C1=0 selects 1-channel auto-scan (CH0 only). Manual mode (AUTO = LOW) uses C3/C2/C1 as static address bits, with channel selected on MXCLK rising edge.

Can ADS8284IBRGCT interface directly with a 3.3-V microcontroller without level shifters?

Yes - ADS8284IBRGCT supports +VBD = 3.3 V operation (per datasheet Section 6.3), and its digital I/O pins (RD, CS, BYTE, BUS18_16, CONVST, BUSY) are CMOS-compatible with 3.3-V logic thresholds. Input VIH min = 2.3 V and VOL max = 0.4 V ensure reliable interfacing with standard 3.3-V MCUs without external level translation.

What is the purpose of the PD-RBUF pin on ADS8284IBRGCT?

The PD-RBUF pin (Pin 21) controls power-down of the BUF-REF output buffer. When PD-RBUF = HIGH, the BUF-REF output is disabled and draws only 10 µA quiescent current - useful for reducing system power during idle periods. Note that PD-RBUF does not 3-state BUF-REF; the output remains at nominal voltage but cannot source significant current.