Texas Instruments ADS1158IRTCR

Overview

ADS1158IRTCR from Texas Instruments is a 16-channel, 16-bit delta-sigma analog-to-digital converter with single-cycle settled data at up to 23.7kSPS per channel, ±2.5V bipolar or +5V unipolar operation, 0.3LSB INL, and integrated 32.768kHz crystal oscillator - used in high-accuracy multi-channel instrumentation systems requiring fast scan and on-chip system monitoring.

For engineers reviewing the ADS1158IRTCR datasheet, ADS1158IRTCR pinout, ADS1158IRTCR application, or ADS1158IRTCR equivalent, key selection criteria include fixed/auto-scan data rate flexibility (1.8–23.7kSPS), differential MUXOUT access for external signal conditioning, GPIO-controlled conversion start, and internal supply/temperature/reference readback capability.

Technical Context

The ADS1158IRTCR employs a fourth-order delta-sigma modulator followed by a fifth-order sinc digital filter optimized for low-noise performance, delivering no missing codes across its 16-bit output. Its flexible 16:1 analog input multiplexer supports 16 single-ended or 8 differential inputs with break-before-make switching in Auto-Scan mode.

On-chip PLL generates a 15.729MHz system clock from a 32.768kHz crystal (via XTAL1/XTAL2) or accepts an external 16MHz clock via CLKIO. The device provides buffered clock output, open-sensor detection via programmable bias current sources (1.5μA/24μA), and real-time monitoring of temperature, AVDD/AVSS, VREF, gain, and offset through dedicated system monitor registers.

Key Specifications

Pinout & Package

ADS1158IRTCR is housed in a 48-pin QFN package (7mm × 7mm, 0.5mm pitch) with exposed thermal pad connected internally to AVSS. Pin assignments are validated per TI SBAS429D Rev. MARCH 2011.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ADS1258IRTCT and AD7606BSTZ, the ADS1158IRTCR uniquely combines per-channel 23.7kSPS scan rate, on-chip crystal oscillator, MUXOUT signal routing, and comprehensive system monitoring - making it optimal for compact, self-diagnosing multi-sensor systems where board space and firmware complexity must be minimized.

Availability

ADS1158IRTCR is available at Aetrix Electronics and suitable for medical sensor arrays, industrial PLC analog input modules, avionics health monitoring units, and test & measurement data loggers requiring stable component supply and long-term production continuity.

Supply support for ADS1158IRTCR 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 signal chain solutions.

The ADS1158IRTCR belongs to TI's high-performance delta-sigma ADC product line, designed specifically for fast-scan, multi-channel instrumentation systems demanding integrated diagnostics, low thermal drift, and flexible input configuration.

FAQ

What is the maximum channel scan rate supported by the ADS1158IRTCR?

The ADS1158IRTCR supports a maximum auto-scan data rate of 23.7kSPS per channel, enabling a complete 16-channel acquisition cycle in under 700μs. This is achieved using its internal fifth-order sinc digital filter and fourth-order delta-sigma modulator. Fixed-channel mode offers higher throughput up to 125kSPS, but only for a single selected input. Both modes deliver single-cycle settled data without additional settling delay - a critical advantage for real-time control loops. The ADS1158IRTCR maintains this performance across its full operating temperature range of –40°C to +105°C.

Does the ADS1158IRTCR require an external crystal oscillator?

No, the ADS1158IRTCR integrates a 32.768kHz crystal oscillator and PLL, allowing it to generate its own 15.729MHz system clock when a crystal is connected to XTAL1/XTAL2 and CLKSEL is low. A 22nF capacitor must be placed between PLLCAP and AVSS. Alternatively, an external 16MHz clock can be applied directly to CLKIO with CLKSEL high. The ADS1158IRTCR does not require external oscillator circuitry - reducing bill-of-materials and PCB area. This dual-clock capability makes the ADS1158IRTCR adaptable to systems with existing clock trees or those requiring autonomous timing.

How does the ADS1158IRTCR support open-sensor detection?

The ADS1158IRTCR implements open-sensor detection using two programmable current sources (1.5μA and 24μA) that can be routed to any analog input channel via register control. When enabled, these sources inject known current into the sensor path; an open circuit results in detectable voltage saturation at the ADC input. The device reports the resulting condition through its system monitor registers, enabling automatic fault flagging without host processor intervention. This feature is factory-characterized and operates across the full –40°C to +105°C range. The ADS1158IRTCR uses this capability to validate sensor integrity in medical and industrial applications where failure detection is safety-critical.

Can the ADS1158IRTCR operate with a bipolar input range?

Yes, the ADS1158IRTCR supports true bipolar operation with a ±2.5V differential input range when powered with AVSS = –2.5V and AVDD = +2.5V. It also supports unipolar +5V operation (AVSS = 0V, AVDD = +5V). The input multiplexer accepts combinations of 16 single-ended or 8 differential inputs in either mode. Full-scale input voltage is defined as ±1.06 × VREF, and the device maintains 0.3LSB INL and 1μV/°C offset drift in both configurations. The ADS1158IRTCR's bipolar capability enables direct interfacing with floating sensors such as thermocouples or bridge transducers without external level-shifting circuitry.

What diagnostic functions are provided by the ADS1158IRTCR's system monitor?

The ADS1158IRTCR's system monitor provides real-time readback of internal die temperature, AVDD and AVSS supply voltages, reference voltage (VREF), gain error, and offset error - all accessible via SPI without external components. These values are stored in dedicated monitor registers and updated continuously during conversion. Temperature sensing uses an on-chip diode with 394μV/°C coefficient; supply readings have ±1% and ±5% error respectively. This integrated diagnostics capability eliminates the need for discrete supervisors or ADCs in space-constrained designs. The ADS1158IRTCR leverages these monitors for self-calibration and fault reporting in mission-critical applications like avionics and process control.