Texas Instruments ADS8328IBRSAR

Overview

ADS8328IBRSAR from Texas Instruments is a 16-bit, 500-kSPS pseudo-differential SAR analog-to-digital converter with integrated 2:1 input multiplexer, programmable TAG bit output, and SPI/DSP-compatible serial interface. It operates from 2.7 V to 5.5 V analog supply, delivers ±1 LSB max DNL and ±1.5 LSB max INL, and supports daisy-chain mode for multi-channel data acquisition in industrial process control systems.

For engineers reviewing the ADS8328IBRSAR datasheet, ADS8328IBRSAR pinout, ADS8328IBRSAR application, or ADS8328IBRSAR equivalent, key selection considerations include its dual-channel pseudo-differential input architecture, 100 dB SFDR at 10 kHz, built-in conversion clock (10.9–12.6 MHz), deep power-down mode (6 nA), and QFN-16 (4×4 mm) package with exposed thermal pad.

Technical Context

The ADS8328IBRSAR implements a capacitor-based successive approximation register (SAR) core with inherent sample-and-hold, supporting both manual and auto-triggered conversion modes. Its 2:1 MUX enables channel selection between +IN0/COM and +IN1/COM, with programmable TAG bit indicating active channel in chain mode.

Conversion timing is governed by an internal CCLK (derived from SCLK or oscillator), requiring 18 CCLK cycles per conversion and 3 CCLK acquisition time. Serial interface complies with SPI Mode 0/3 and TMS320 DSP frame sync protocols, supporting up to 21 MHz SCLK when used as I/O clock only.

Key Specifications

Pinout & Package

The ADS8328IBRSAR is housed in a 16-pin QFN package (4 mm × 4 mm, RSA designation) with wettable flank leads and an exposed thermal pad internally connected to substrate (recommended to connect to AGND).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 16-bit SAR ADC applications.

Compared with ADS8327IBRSAR and AD7682BCPZ, the ADS8328IBRSAR uniquely combines dual-channel pseudo-differential input, embedded TAG bit, and internal CCLK - enabling compact, synchronized multi-sensor acquisition without external timing or logic.

Availability

ADS8328IBRSAR is available at Aetrix Electronics and suitable for industrial process control, medical instrumentation, magnetometer signal conditioning, and automatic test equipment requiring stable component supply and long-term manufacturability.

Supply support for ADS8328IBRSAR 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and personal electronics markets.

The ADS8328 belongs to TI's precision SAR ADC product line, engineered for high-resolution data acquisition in noise-sensitive, power-constrained, and space-limited applications requiring true 16-bit performance without calibration.

FAQ

What is the maximum external SCLK frequency supported by the ADS8328IBRSAR?

The ADS8328IBRSAR supports up to 50 MHz SCLK when used solely as an I/O clock, and up to 21 MHz when SCLK also serves as the conversion clock source. At 21 MHz, the device achieves its rated 500 kSPS throughput with 18-cycle conversion time and 3-cycle acquisition window, ensuring deterministic timing for real-time control loops.

Does the ADS8328IBRSAR require an external reference voltage?

Yes, the ADS8328IBRSAR requires an external reference applied between REF+ and REF− pins. It accepts 2.5 V or 4.096 V references depending on analog supply voltage (+VA), with REF− tied directly to AGND. No internal reference is provided; accuracy and stability depend entirely on the external reference source.

How does the programmable TAG bit function in the ADS8328IBRSAR?

The TAG bit in ADS8328IBRSAR is a configurable output appended to each 16-bit conversion result, indicating which input channel (+IN0 or +IN1) was sampled. In daisy-chain mode, it enables unambiguous channel identification across multiple devices without additional GPIO or software tracking - critical for synchronized multi-sensor systems.

What are the power-down current levels for the ADS8328IBRSAR?

The ADS8328IBRSAR offers three power-down states: Deep power-down draws 6 nA typical (max 50 nA), Nap mode consumes 0.3 mA typical (max 0.5 mA), and Auto-Nap automatically enters/exits Nap based on CONVST activity. These modes allow dynamic power scaling in battery-powered or thermally constrained applications while preserving configuration registers.

Can the ADS8328IBRSAR operate with separate analog and digital supply voltages?

Yes, the ADS8328IBRSAR uses independent supplies: +VA (2.7 V to 5.5 V) powers the analog core and reference circuitry, while +VBD (1.65 V to 5.5 V) powers digital I/O buffers. This separation allows level-shifting between host processor logic and ADC interface, reduces digital switching noise coupling into analog sections, and supports mixed-voltage system architectures.