Texas Instruments ADS1146IPW

Overview

ADS1146IPW from Texas Instruments is a 16-bit, 2-kSPS delta-sigma analog-to-digital converter (ADC) with integrated programmable gain amplifier (PGA), single-cycle settling digital filter, and internal oscillator - designed for high-precision sensor front-end applications requiring one differential input pair, external reference, and no excitation current sources. It operates from 2.7 V to 5.25 V analog supply and supports simultaneous 50-Hz/60-Hz rejection at 20 SPS in RTD and thermocouple measurement systems.

For engineers reviewing the ADS1146IPW datasheet, ADS1146IPW pinout, ADS1146IPW application, or ADS1146IPW equivalent, this page delivers verified technical context, confirmed pin functions, real-world use cases in industrial sensing, and validated alternative options - all grounded in TI's SBAS453G production datasheet and official package documentation.

Technical Context

The ADS1146IPW implements a third-order delta-sigma modulator with a digitally programmable FIR filter that settles in one conversion cycle, enabling fast channel cycling without settling delay. Its PGA offers eight selectable gains (1× to 128×) and supports unipolar (2.7–5.25 V) or bipolar (±2.5 V) analog supplies.

Unlike ADS1147/ADS1148, the ADS1146IPW lacks internal voltage reference, dual IDACs, GPIOs, burnout detection, and multiplexer inputs - it accepts only one differential analog input (AINP/AINN) and requires external REFP/REFN. Its serial interface is SPI-compatible with active-low CS, START-triggered conversion, and DOUT/DRDY dual-function output.

Key Specifications

Pinout & Package

TSSOP-16 (PW) package: 5.00 mm × 4.40 mm body, 0.65 mm pitch, exposed thermal pad (not connected in ADS1146IPW per datasheet).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision ADC applications.

Compared with ADS1147IPW, the ADS1146IPW reduces component count in single-sensor systems by omitting redundant features, while ADS1246IPW trades simplicity and power efficiency for resolution - making ADS1146IPW optimal for cost-sensitive, space-constrained industrial sensor nodes.

Availability

ADS1146IPW is available at Aetrix Electronics and suitable for RTD temperature monitoring, thermocouple signal conditioning, bridge-based pressure sensing, factory automation analog input modules, and industrial process control systems requiring stable component supply and long-term manufacturability.

Supply support for ADS1146IPW 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 sensor interface solutions.

The ADS114x family was engineered specifically for high-accuracy, low-power sensor measurement in industrial and instrumentation applications - the ADS1146IPW serves as the entry-level, single-channel variant optimized for minimal BOM and layout complexity.

FAQ

Does the ADS1146IPW include an internal voltage reference?

No, the ADS1146IPW requires external REFP and REFN connections - unlike ADS1147/ADS1148, it does not integrate a 2.048-V reference. This simplifies the die but mandates a stable external reference (e.g., REF5025 or REF6025) for full-scale accuracy. The ADS1146IPW datasheet explicitly states "external reference only" in the device comparison table and functional description.

What is the maximum achievable data rate for the ADS1146IPW?

The ADS1146IPW supports data rates from 5 SPS up to 2000 SPS, with 2000 SPS being the absolute maximum. At 2000 SPS, the digital filter provides single-cycle settling but does not perform 50/60 Hz rejection - that capability is limited to ≤20 SPS per the SBAS453G datasheet timing specifications and filter response characterization.

Can the ADS1146IPW drive a 4-wire RTD directly?

No, the ADS1146IPW cannot drive a 4-wire RTD directly because it lacks integrated excitation current sources (IDACs). Unlike ADS1147/ADS1148, the ADS1146IPW has no IEXC pins. A 4-wire RTD interface requires external precision current sources and Kelvin sensing - the ADS1146IPW only conditions the resulting differential voltage at AINP/AINN.

Is the ADS1146IPW pin-compatible with ADS1147IPW or ADS1148IPW?

No, the ADS1146IPW (TSSOP-16) is not pin-compatible with ADS1147IPW (TSSOP-20) or ADS1148IPW (TSSOP-28/VQFN-32). Pin counts, pin functions, and package dimensions differ significantly - e.g., ADS1146IPW has no GPIO, IDAC, or VREFOUT pins. Migration requires PCB redesign and firmware adaptation.

What is the purpose of the CLK pin on the ADS1146IPW?

The CLK pin on the ADS1146IPW accepts an external clock signal to override the internal 4.096-MHz oscillator. When unused, CLK must be tied to DGND to enable the internal clock - it is not an output. This flexibility allows synchronization to system clocks or reduction of EMI in noise-sensitive environments, as documented in Section 6.1 of SBAS453G.