Texas Instruments ADS1118IRUGT

Overview

ADS1118IRUGT from Texas Instruments is a precision 16-bit SPI-compatible analog-to-digital converter with integrated PGA, internal voltage reference, oscillator, and high-accuracy temperature sensor. It supports four single-ended or two differential inputs, operates from 2 V to 5.5 V, achieves up to 860 SPS, and delivers ±0.5°C temperature accuracy (0°C to 70°C) - enabling compact, low-power sensor measurement in space-constrained industrial systems.

For engineers reviewing the ADS1118IRUGT datasheet, ADS1118IRUGT pinout, ADS1118IRUGT application, or ADS1118IRUGT equivalent, key selection considerations include its X2QFN-10 package (2 mm × 1.5 mm), programmable gain (±256 mV to ±6.144 V FSR), single-cycle settling, automatic power-down in single-shot mode (150 μA continuous), and integrated cold-junction compensation capability for thermocouple interfaces.

Technical Context

The ADS1118IRUGT implements a sigma-delta ADC architecture with an on-chip programmable gain amplifier (PGA) that scales input signals prior to conversion, supporting full-scale ranges from ±256 mV to ±6.144 V. Its internal oscillator eliminates external timing components, while the integrated temperature sensor provides direct die-temperature readings with 0.03125°C/LSB resolution.

It uses a 4-wire SPI interface (SCLK, CS, DIN, DOUT/DRDY) with data-ready signaling and supports both continuous and single-shot conversion modes. The device features an input multiplexer selecting among AIN0–AIN3, and its internal reference exhibits low drift over temperature and supply variation.

Key Specifications

Pinout & Package

ADS1118IRUGT is housed in an ultrasmall 10-pin X2QFN package (2.00 mm × 1.50 mm × 0.40 mm), optimized for space-constrained PCB layouts and thermal performance (RθJA = 245.2°C/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar analog-to-digital conversion applications.

Compared with ADS1118IDGST, the ADS1118IRUGT offers 40% smaller PCB footprint and improved thermal performance at the cost of reduced manufacturability; versus ADS1018IRUGT, it trades speed for 16-bit precision and enhanced DC accuracy - making ADS1118IRUGT optimal for high-resolution, low-power sensor digitization where size and thermal constraints dominate.

Availability

ADS1118IRUGT is available at Aetrix Electronics and suitable for factory automation I/O modules, portable environmental monitors, and medical sensor interfaces requiring stable component supply and long-term production continuity.

Supply support for ADS1118IRUGT 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 company specializing in analog and embedded processing technologies, with leadership in precision data converters and industrial-grade ICs.

The ADS1118IRUGT belongs to TI's precision delta-sigma ADC product line, designed specifically for high-accuracy, low-power sensor signal acquisition in harsh industrial and portable environments.

FAQ

What is the operating temperature range of the ADS1118IRUGT?

The ADS1118IRUGT is specified to operate across an ambient temperature range of –40°C to +125°C. This extended range supports deployment in demanding industrial environments such as motor control cabinets, outdoor process instrumentation, and automotive under-hood sensor nodes - all while maintaining its ±0.5°C temperature sensor accuracy within 0°C to 70°C and full 16-bit ADC performance throughout the full range.

Does the ADS1118IRUGT require an external crystal or clock source?

No, the ADS1118IRUGT does not require an external crystal or clock source. It integrates a precision internal oscillator that drives the ADC and SPI interface, eliminating external timing components and reducing bill-of-materials cost and PCB area. This internal oscillator supports all data rates from 8 SPS to 860 SPS without external dependency, and its stability is characterized across the full –40°C to +125°C temperature range.

How does the ADS1118IRUGT handle cold-junction compensation for thermocouples?

The ADS1118IRUGT performs cold-junction compensation by simultaneously digitizing the thermocouple voltage (e.g., on AIN0–AIN1 differential pair) and reading its integrated on-die temperature sensor. The sensor provides 0.03125°C/LSB resolution and ±0.5°C accuracy (0°C to 70°C), allowing firmware to compute compensated thermocouple temperature using standard NIST polynomials. No external temperature sensor or additional ADC channel is needed - the entire function resides within the ADS1118IRUGT.

What are the power supply decoupling requirements for the ADS1118IRUGT?

The ADS1118IRUGT requires a 100-nF ceramic capacitor placed as close as possible between the VDD and GND pins to suppress high-frequency noise and ensure stable reference and oscillator operation. This decoupling is mandatory per TI's layout guidelines and directly impacts INL, offset drift, and temperature sensor accuracy. Additional bulk capacitance (e.g., 1–10 μF) may be added upstream but does not replace the local 100-nF requirement. The device draws only 150 μA in continuous mode, minimizing IR drop concerns.

Can the ADS1118IRUGT interface directly with a 5 V microcontroller SPI bus?

Yes, the ADS1118IRUGT supports digital I/O voltage levels compatible with 5 V microcontrollers: VIH = 0.7 × VDD and VIL = 0.2 × VDD, meaning at VDD = 5 V, it accepts 3.5 V as high and 1 V as low - fully compatible with standard 5 V logic. Its absolute maximum digital input voltage is VDD + 0.3 V, so connecting SCLK, CS, and DIN directly to a 5 V MCU is safe when ADS1118IRUGT's VDD is also 5 V. DOUT/DRDY output swings rail-to-rail and drives 1 mA, ensuring robust level matching.