Texas Instruments ADS8331IRGER

Overview

ADS8331IRGER from Texas Instruments is a low-power, 16-bit, 500-kSPS unipolar-input SAR analog-to-digital converter with integrated 4-channel multiplexer, on-chip conversion clock, and SPI/DSP-compatible serial interface. It features ±1.2 LSB typical INL, 91.5-dB SNR at 1 kHz (5 V), 2.7–5.5 V analog supply, and operates across –40°C to +85°C for industrial data acquisition systems.

For engineers reviewing the ADS8331IRGER datasheet, ADS8331IRGER pinout, ADS8331IRGER application, or ADS8331IRGER equivalent, key selection considerations include its 4-channel mux architecture, daisy-chain capability, programmable EOC/INT polarity, deep power-down mode (250 nA), and dual-supply flexibility (VA up to 5.5 V, VBD from 1.65 V).

Technical Context

The ADS8331IRGER implements a capacitor-based successive approximation register (SAR) ADC with inherent sample-and-hold, supporting both manual and auto-triggered conversions via CONVST or global CONVST. Its internal 11-MHz conversion clock eliminates external timing components, while flexible trigger modes (manual/auto) and channel-select logic enable deterministic sampling in multi-sensor systems.

It supports SPI- and DSP-style serial protocols via FS/CS framing, with configurable SDO output polarity, programmable status signaling on EOC/INT/CDI, and daisy-chain operation for synchronized multi-ADC readouts. The device uses straight-binary output format and maintains 16-bit no-missing-codes performance over temperature.

Key Specifications

Pinout & Package

ADS8331IRGER is packaged in a 24-pin VQFN (RGE) with 4.00 mm × 4.00 mm body and exposed thermal pad (to be connected to AGND). Pin count and layout match the TSSOP-24 variant, enabling footprint compatibility in space-constrained PCBs.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS8332IRGER, the ADS8331IRGER saves PCB area by omitting unused IN4–IN7 traces and simplifies firmware for 4-channel systems; versus ADS8684IPWR, it offers wider supply flexibility and lower quiescent current but requires external reference management.

Availability

ADS8331IRGER is available at Aetrix Electronics and suitable for industrial process controls, medical instrumentation, automated test equipment, and magnetometer data acquisition requiring stable component supply and long-term manufacturability.

Supply support for ADS8331IRGER 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, embedded processing, and connectivity technologies with decades of precision data converter innovation.

The ADS833x family was designed for low-power, high-accuracy industrial and medical data acquisition where channel integration, serial interface flexibility, and thermal efficiency are critical.

FAQ

What is the maximum SCLK frequency supported by the ADS8331IRGER?

The ADS8331IRGER supports up to 40 MHz SCLK when used solely as an I/O clock at VA = VBD = 5 V. When SCLK also serves as the conversion clock, the maximum is 21 MHz. At 2.7 V operation, the I/O-only limit drops to 25 MHz. These values are specified in the Electrical Characteristics tables and validated across the full –40°C to +85°C temperature range for the ADS8331IRGER.

Does the ADS8331IRGER require an external reference voltage?

Yes, the ADS8331IRGER requires an external reference applied between REF+ and REF− pins. It accepts references from 1.2 V to 4.2 V (at 5 V VA) and supports both buffered and unbuffered sources. The device does not include an internal reference; therefore, a precision external reference such as REF3240 is required for metrology-grade accuracy in the ADS8331IRGER.

How does the power consumption of the ADS8331IRGER scale with sampling rate?

The ADS8331IRGER draws 6.5 mA analog current at 500 kSPS (VA = 2.7 V), dropping to 3.2 mA in Auto-NAP mode at 250 kSPS, and further to 325 µA in Nap mode. Deep power-down reduces current to 250 nA. This scalable consumption enables dynamic power management in battery-operated ADS8331IRGER systems without sacrificing conversion integrity.

Can the ADS8331IRGER operate with separate analog and digital supply voltages?

Yes, the ADS8331IRGER features independent VA (2.7–5.5 V, analog core) and VBD (1.65–VA, digital I/O) supplies. This allows interfacing with 1.8-V FPGAs or 3.3-V microcontrollers while powering the ADC core from a clean 3.0-V rail-reducing noise coupling and simplifying power domain partitioning in mixed-signal ADS8331IRGER designs.

What is the purpose of the MUXOUT pin on the ADS8331IRGER?

The MUXOUT pin on the ADS8331IRGER provides access to the output of the internal 4:1 analog multiplexer, prior to the ADC's sample-and-hold stage. This allows external circuitry-such as anti-alias filtering, gain stages, or diagnostic monitoring-to be placed between the mux and ADCIN, enhancing signal integrity and debug visibility in the ADS8331IRGER signal chain.