ADS131E08SPAGR: 8-Channel 24-Bit Delta-Sigma AFE

Designed as a highly integrated 8-channel, 24-bit analog front-end (AFE), the ADS131E08SPAGR is a simultaneous-sampling, delta-sigma (ΔΣ) analog-to-digital converter from Texas Instruments' ADS131E08S family. Categorized as a precision measurement IC optimized for industrial power monitoring and protection, this device is available in a 64-pin TQFP (PAG) surface-mount package measuring 10.00 mm × 10.00 mm, well-suited for high-density PCB layouts. By integrating eight differential simultaneous-sampling inputs, built-in programmable gain amplifiers (PGAs), an internal voltage reference, and an onboard oscillator into a single chip, the ADS131E08S enables system designers to build scalable industrial power systems with significantly reduced size, power, and overall cost.

The core advantage of this 24-bit delta-sigma ADC lies in its fast 3 ms power-up time, which allows data to be available within just 3 milliseconds of power being applied to the device-a critical requirement for line-powered protection applications where rapid response is essential[reference:0][reference:1]. The ADC achieves a dynamic range of 118 dB at 1 kSPS, crosstalk of –125 dB, and total harmonic distortion (THD) of –100 dB at 50 Hz and 60 Hz, delivering outstanding measurement integrity for precision power monitoring[reference:2]. With power consumption of only 2 mW per channel, the device balances high performance with energy efficiency, making it ideal for multi-channel industrial systems[reference:3].

At the heart of the ADS131E08S is an eight-channel simultaneous-sampling architecture, with each channel featuring an independent input multiplexer that can be connected to internally generated signals for test, temperature, and fault detection[reference:4]. The device supports data rates of 1, 2, 4, 8, 16, 32, and 64 kSPS, with gain options of 1, 2, 4, 8, and 12[reference:5]. True high-impedance inputs enable the ADS131E08S to directly interface with a resistor-divider network or voltage transformer to measure line voltage, or a current transformer or Rogowski coil to measure line current, eliminating the need for external signal conditioning circuitry[reference:6]. The internal voltage reference features an exceptionally low drift of 8 ppm/°C, ensuring stable performance over temperature variations[reference:7].

The ADS131E08S is equipped with comprehensive fault detection and self-testing capabilities as standard configurations. Fault detection can be implemented internally using integrated comparators with digital-to-analog converter (DAC)-controlled trigger levels, enabling the device to autonomously identify abnormal conditions on any input channel[reference:8]. The ADC also includes a device self-testing capability, which allows system designers to verify measurement integrity without external test equipment. A SPI-compatible data interface and four general-purpose input/output (GPIO) pins provide flexible connectivity to microcontrollers and DSPs[reference:9].

The ADS131E08SPAGR variant operates from an analog supply range of 2.7V to 5.25V (unipolar) or ±2.5V (bipolar), with a digital supply range of 1.7V to 3.6V[reference:10]. Its operating temperature range covers ‑40°C to 105°C, ensuring stable performance under the harsh environmental conditions typical of industrial power monitoring, control, and protection applications[reference:11]. The device is rated for RoHS and REACH compliance, with a NiPdAu lead finish and MSL Level-3-260C-168 HR moisture sensitivity rating[reference:12]. The ADS131E08SPAGR is supplied in tape-and-reel packaging with a standard pack quantity (SPQ) of 1500 units, reel diameter of 330 mm, and reel width of 24.4 mm, optimized for high-volume automated assembly[reference:13].

Product variant comparison - The ADS131E08S family is offered in multiple orderable variants that differ primarily in power-up time, reference configuration, and packaging format. The ADS131E08S variant (ordering code ADS131E08SPAGR) features a fast 3 ms power-up time and an internal-only voltage reference, making it ideal for line-powered protection applications that require rapid startup[reference:14]. The standard ADS131E08 variant offers a 128 ms power-up time with both internal and external reference options, suitable for applications where startup speed is less critical[reference:15]. Both variants share the same 64-pin TQFP (PAG) package, eight differential simultaneous-sampling inputs, 24-bit resolution, and 64 kSPS maximum data rate. The following table summarises the key differentiators among ADS131E08 family orderable variants:

For replacement considerations, the ADS131E08IPAGR is the industrial-grade variant with a wider temperature range, while the ADS131E08SPAGR remains the preferred choice for applications requiring the fastest possible power-up time. TI's broader ADS131E0x family includes the ADS131E04 (4-channel) and ADS131E06 (6-channel) variants, offering scalable channel counts for different system requirements[reference:16]. For applications requiring alternative sampling rates or interfaces, the ADS131M08 and ADS131M04 provide lower sampling rates (32 kSPS) at reduced cost points, while maintaining the same 24-bit resolution and delta-sigma architecture[reference:17]. All ADS131E08 family variants share the same TQFP-64 footprint, enabling straightforward design migration between channel counts and feature configurations without PCB layout changes.

Common application scenarios for this 8-channel, 24-bit analog front-end include industrial power monitoring and protection, three-phase voltage and current measurement, electronic trip units (ETUs) in circuit breakers, energy metering, power quality analysis, and industrial control systems[reference:18][reference:19]. Typical use cases involve building multi-phase power monitoring systems that simultaneously sample voltage and current on all phases, implementing fault detection in circuit breakers and protection relays, and designing high-precision energy meters that require wide dynamic range and low crosstalk. The device's fast 3 ms power-up time makes it particularly valuable for line-powered protection applications where immediate data availability after power-on is critical. Thanks to its eight-channel simultaneous-sampling architecture, 118 dB dynamic range, integrated fault detection, and fast power-up capability, the ADS131E08SPAGR has become a trusted choice for engineers seeking a versatile, high-performance 24-bit delta-sigma ADC-one that delivers the measurement precision and channel density required for mission-critical industrial power systems, all while maintaining the integration level and design simplicity of a single analog front-end IC.