Texas Instruments ADS1252U/2K5G4

Overview

ADS1252U/2K5G4 from Texas Instruments is a 24-bit delta-sigma analog-to-digital converter (ADC) with no missing codes, 19-bit effective resolution at up to 40kHz data rate, and 2.5ppm rms noise. It operates from a single +5V supply, features differential inputs, external reference support (0.5V–5V), and integrated sinc5 digital filtering. It is used in high-precision cardiac diagnostics, chromatography, and industrial process control systems.

For engineers reviewing the ADS1252U/2K5G4 datasheet, ADS1252U/2K5G4 pinout, ADS1252U/2K5G4 application, or ADS1252U/2K5G4 equivalent, this page delivers verified technical context, SO-8 package mapping, real-world timing and noise performance, and validated alternative options for precision measurement designs requiring stable 24-bit conversion at ≤40kHz.

Technical Context

The ADS1252U/2K5G4 employs a 4th-order delta-sigma modulator with fixed 64× oversampling ratio and a sinc5 digital filter that scales linearly with system clock frequency. Its modulator clock is derived as CLK ÷ 6, enabling precise notch placement at integer multiples of the data output rate - critical for 50Hz/60Hz power-line rejection.

It uses a fully differential switched-capacitor input architecture delivering 100dB common-mode rejection at DC and supports bipolar input configurations via external level-shifting circuitry. The device implements synchronous serial communication with dual-mode DOUT/DRDY pin and Schmitt-trigger clock inputs (CLK and SCLK), allowing independent clock domains and flexible isolation.

Key Specifications

Pinout & Package

ADS1252U/2K5G4 is housed in an SO-8 (Small Outline) package with gull-wing leads, rated for –40°C to +85°C operation. Pin 1 is marked with a dot or beveled edge; thermal pad is not present.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-resolution delta-sigma ADC applications.

Compared with ADS1252U/2K5G4, ADS1256IPWR offers channel density and PGA integration at lower per-channel data rate, while AD7730BRUZ provides excitation capability but sacrifices notch tuning and speed - making ADS1252U/2K5G4 optimal for single-channel, high-speed, noise-critical applications demanding precise digital filtering control.

Availability

ADS1252U/2K5G4 is available at Aetrix Electronics and suitable for cardiac diagnostics equipment, chromatography detectors, industrial weigh scales, and portable instrumentation requiring stable component supply across extended production lifecycles.

Supply support for ADS1252U/2K5G4 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 signal chains.

The ADS1252U/2K5G4 belongs to TI's high-accuracy delta-sigma ADC family designed for applications demanding 24-bit integrity, low drift, and flexible digital filtering - particularly in medical, analytical, and process control instrumentation.

FAQ

What is the maximum data rate supported by the ADS1252U/2K5G4?

The ADS1252U/2K5G4 achieves a maximum data rate of 41.667 kHz when driven by a 16 MHz system clock (CLK). This is derived from the modulator clock (CLK ÷ 6 = 2.667 MHz) and fixed 64× oversampling ratio. Lower CLK frequencies proportionally reduce data rate - e.g., 15.36 MHz yields exactly 40 kHz - enabling precise alignment with 50/60 Hz rejection requirements. The ADS1252U/2K5G4 maintains 19-bit effective resolution up to this 40 kHz threshold.

Does the ADS1252U/2K5G4 support bipolar input signals referenced to ground?

Yes, the ADS1252U/2K5G4 supports bipolar inputs via external level-shifting circuitry. Its differential inputs accept signals where +VIN and –VIN each stay within –0.3 V to VDD + 0.3 V. Using a single op amp (e.g., OPA2350) and four resistors, standard ±2.5 V, ±5 V, or ±10 V ranges can be mapped to the ADS1252U/2K5G4's input range. The device itself does not generate negative supply rails - bipolar operation relies entirely on external signal conditioning before the +VIN/–VIN pins.

How does the sinc5 digital filter in the ADS1252U/2K5G4 enable power-line frequency rejection?

The sinc5 filter in the ADS1252U/2K5G4 places sharp notches at integer multiples of the data output rate (e.g., at 50 Hz, 100 Hz, 150 Hz). By setting the data rate to 50 Hz (via 19.2 kHz CLK) or 60 Hz (via 20.04 kHz CLK), fundamental power-line interference is attenuated >100 dB. A 10 Hz data rate rejects both 50 Hz and 60 Hz simultaneously with >135 dB attenuation. This eliminates need for external analog notch filters and simplifies system design - a core capability confirmed in the ADS1252U/2K5G4's theory-of-operation section.

What is the purpose of the DOUT/DRDY pin on the ADS1252U/2K5G4?

The DOUT/DRDY pin on the ADS1252U/2K5G4 serves two time-multiplexed functions: it asserts LOW to signal "Data Ready" (DRDY mode), then shifts out the 24-bit conversion result MSB-first on its falling edge synchronized to SCLK (DOUT mode). This dual-role design reduces pin count while maintaining deterministic timing - the ADS1252U/2K5G4 requires reading all 24 bits before the next DRDY pulse to avoid data loss. The pin's behavior is fully defined in timing Table II and Figures 11–12 of the official datasheet.

Can the ADS1252U/2K5G4 operate with a reference voltage below 1 V?

Yes, the ADS1252U/2K5G4 supports reference voltages from 0.5 V to 5 V. At 0.5 V VREF, full-scale differential input range is ±0.5 V, and rms noise remains 2.5 ppm of that full scale - i.e., ~12.5 nV rms. However, lower VREF increases sensitivity to reference noise and drift; TI recommends using a buffered, low-noise reference (e.g., REF3140) and the circuit in Figure 2 for optimal performance. The ADS1252U/2K5G4's 220 µA reference load current scales linearly with CLK frequency, so lower CLK further reduces reference burden.