Texas Instruments ADS1158IRTCTG4

Overview

ADS1158IRTCTG4 from Texas Instruments is a 16-channel, 16-bit delta-sigma analog-to-digital converter with single-cycle settled data at up to 23.7 kSPS per channel, ±2.5V bipolar or +5V unipolar input range, 0.3 LSB INL, and integrated 32.768 kHz crystal oscillator for clock generation - used in high-resolution industrial process monitoring systems requiring fast multi-channel scanning.

For engineers reviewing the ADS1158IRTCTG4 datasheet, ADS1158IRTCTG4 pinout, ADS1158IRTCTG4 application, or ADS1158IRTCTG4 equivalent, key selection criteria include fixed/auto-scan data rate flexibility (1.95–23.7 kSPS), on-chip temperature/reference/supply monitoring, GPIO[7:0] control, MUXOUTP/MUXOUTN for external signal conditioning, and QFN-48 package compatibility with precision layout requirements.

Technical Context

The ADS1158IRTCTG4 employs a fourth-order delta-sigma modulator followed by a fifth-order sinc digital filter, delivering no missing codes and 0.6 LSB peak-to-peak noise. Its 16:1 analog multiplexer supports 16 single-ended or 8 differential inputs with programmable sensor bias current sources (1.5 µA or 24 µA) and open-sensor detection.

Internal system monitoring registers provide real-time readback of on-die temperature (394 µV/°C), AVDD/AVSS supply voltage, VREF, gain, and offset. Clocking is configurable via internal PLL-driven 32.768 kHz crystal (XTAL1/XTAL2) or external 16 MHz source on CLKIO, with 15.729 MHz buffered clock output available for synchronizing external controllers.

Key Specifications

Pinout & Package

ADS1158IRTCTG4 is housed in a thermally enhanced 48-pin QFN package (7 mm × 7 mm, 0.5 mm pitch) with exposed thermal pad internally connected to AVSS. Pin assignments are fully defined per TI SBAS429D Rev. D.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS1258IRTCT and AD7606BSTZ, the ADS1158IRTCTG4 uniquely combines 16-bit precision, 16:1 MUX, integrated 32.768 kHz oscillator, 8 GPIOs, and on-die system monitoring - making it optimal for embedded, space-constrained, multi-sensor systems where self-contained timing and diagnostics are essential.

Availability

ADS1158IRTCTG4 is available at Aetrix Electronics and suitable for industrial process control, medical instrumentation, and avionics health monitoring requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for ADS1158IRTCTG4 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 IC design.

The ADS1158IRTCTG4 belongs to TI's high-performance delta-sigma ADC product line, engineered specifically for fast-scan, multi-channel, high-accuracy measurement systems in harsh industrial and medical environments.

FAQ

What is the maximum channel scan rate supported by the ADS1158IRTCTG4 in Auto-Scan mode?

The ADS1158IRTCTG4 achieves a maximum channel scan rate of 23.7 kSPS per channel in Auto-Scan mode, completing a full 16-channel sequence in under 700 µs. This performance is guaranteed with the internal PLL clock enabled and proper external signal conditioning. The ADS1158IRTCTG4 maintains single-cycle settled data at this rate, eliminating post-processing settling delays in time-critical applications.

Does the ADS1158IRTCTG4 require an external crystal, or can it operate with an external clock source?

The ADS1158IRTCTG4 supports both clocking methods: a 32.768 kHz crystal connected to XTAL1/XTAL2 (with 22 nF PLLCAP to AVSS) or an external 16 MHz clock applied to CLKIO. The CLKSEL pin selects the source - low for crystal oscillator, high for external clock. The ADS1158IRTCTG4's internal PLL generates a precise 15.729 MHz system clock in either configuration, and CLKIO can output this clock for synchronizing other devices.

How does the ADS1158IRTCTG4 handle reference voltage monitoring and what accuracy is specified?

ADS1158IRTCTG4 integrates a dedicated reference voltage monitor that reads back VREF = (VREFP – VREFN) with ±3% error across temperature. This reading is accessible via internal system monitor registers and enables real-time correction of gain drift in software. The ADS1158IRTCTG4's 2 ppm/°C gain drift specification ensures long-term stability, and the monitored reference value allows closed-loop calibration even during operation.

Can the ADS1158IRTCTG4's GPIO pins be used for sensor bias current control, and what current levels are available?

Yes - the ADS1158IRTCTG4 includes programmable sensor bias current sources controllable via register settings, not directly via GPIO pins. Two precision levels are available: 1.5 µA and 24 µA, with a 1% ratio error between them. These currents are routed through the analog input multiplexer to bias RTDs, thermistors, or bridge sensors. The ADS1158IRTCTG4 uses these sources for both excitation and open-sensor detection, providing hardware-level fault awareness without additional circuitry.

What is the absolute input voltage range allowed on the AINx pins of the ADS1158IRTCTG4 relative to AVSS and AVDD?

The ADS1158IRTCTG4 specifies an absolute analog input voltage range of AVSS – 100 mV to AVDD + 100 mV on all AINx pins, including AINCOM. This 200 mV overvoltage tolerance protects the internal switched-capacitor front-end from transient damage and prevents ESD diode conduction during normal operation. Exceeding this range risks inaccurate conversions or latch-up. The ADS1158IRTCTG4's input structure presents ~40 kΩ effective impedance at 16 MHz clock, requiring appropriate driver strength for full 16-bit accuracy.