Analog Devices Inc. ADFS7124-8BBCPZ

Overview

ADFS7124-8BBCPZ from Analog Devices is a 24-bit sigma-delta ADC with integrated PGA, internal reference, excitation currents, bias voltage generator, and diagnostic suite-designed for high-precision industrial sensor measurement. It delivers 24 nV rms noise at 1.17 SPS (low power mode), supports 8 differential or 15 pseudodifferential inputs, operates from −40°C to +125°C, and targets applications such as RTD-based temperature transmitters and bridge-based pressure sensors.

For engineers reviewing the ADFS7124-8BBCPZ datasheet, ADFS7124-8BBCPZ pinout, ADFS7124-8BBCPZ application, or ADFS7124-8BBCPZ equivalent, key selection criteria include simultaneous 50/60 Hz rejection at 25 SPS, per-channel configuration support (gain/filter/ODR), functional safety certification (TÜV SC3), and integrated diagnostics enabling SIL-certifiable designs without external monitoring circuitry.

Technical Context

The ADFS7124-8BBCPZ implements a multi-stage sigma-delta modulator with selectable sinc3/sinc4/fast-settling/post filters, supporting programmable output data rates from 1.17 SPS to 19.2 kSPS across three power modes. Its analog front end includes rail-to-rail input buffers (enabled automatically for gain > 1), matched 0.1–1000 µA excitation current sources, and a low-drift (15 ppm/°C) internal band gap reference.

It integrates a 16-channel automatic sequencer with per-channel register sets (gain, filter, ODR, reference), enabling interleaved conversion and diagnostics. The device features dual LDOs (ALDO/DLDO), burnout detection, CRC-protected memory map, and comprehensive fault reporting-including reference detect, overvoltage/undervoltage on AINx, and SPI read/write error capture.

Key Specifications

Pinout & Package

ADFS7124-8BBCPZ is housed in a 32-lead, 5 mm × 5 mm, 0.8 mm pitch LFCSP package with exposed thermal pad (EP). Pin functions are defined per Analog Devices Rev. A datasheet, Section "Pin Configuration and Function Descriptions" (p. 15).

Key Features

Applications

Equivalent & Alternatives

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

Compared with AD7177-2 and ADS1263, the ADFS7124-8BBCPZ uniquely combines TÜV SC3 certification, per-channel configuration, and guaranteed 80 dB simultaneous 50/60 Hz rejection at 25 SPS-making it the only option for SIL2-compliant, multi-sensor, line-noise-immune industrial transmitters without external filtering or safety co-processors.

Availability

ADFS7124-8BBCPZ is available at Aetrix Electronics and suitable for industrial process control, smart transmitter design, and high-reliability temperature/pressure measurement systems requiring stable component supply, long lifecycle support, and traceable sourcing.

Supply support for ADFS7124-8BBCPZ 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

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets since 1965.

The ADFS7124-8BBCPZ belongs to Analog Devices' ADFS family of functional-safety-certified, highly integrated analog front ends-designed specifically for SIL2/SIL3 industrial sensor signal conditioning in harsh environments.

FAQ

What is the maximum simultaneous 50 Hz and 60 Hz rejection capability of the ADFS7124-8BBCPZ?

The ADFS7124-8BBCPZ achieves ≥80 dB simultaneous 50 Hz and 60 Hz rejection at an output data rate of 25 SPS with single-cycle settling-using its sinc4 filter and internal clock. This performance is confirmed in the datasheet's "Normal Mode Rejection" table (p. 6) and eliminates the need for external notch filters in AC-line-noise-prone industrial installations. The ADFS7124-8BBCPZ maintains this rejection across temperature and supply variations without recalibration.

Does the ADFS7124-8BBCPZ support per-channel configuration for different gains and filters?

Yes, the ADFS7124-8BBCPZ supports eight independent channel configurations, each defining gain (1–128), filter type (sinc3/sinc4/fast-settling/post), output data rate, buffering, and reference source. These setups can be assigned on a channel-by-channel basis-enabling mixed-sensor systems (e.g., RTD, thermocouple, voltage) within a single ADFS7124-8BBCPZ acquisition frame. Configuration is stored in dedicated channel registers (p. 89–91 of datasheet).

What functional safety certifications does the ADFS7124-8BBCPZ hold?

The ADFS7124-8BBCPZ is functionally safety approved to SC3 by TÜV Rheinland (File No. 968/FSP 2188.01/23) and supports IEC 61508 SIL2/SIL3 system design. Its FMEDA reports a safe failure fraction >90%, enabled by integrated diagnostics including CRC-protected registers, signal chain checks, reference detect, and SPI error logging-all documented in the ADFS7124-8BBCPZ datasheet Sections 69–72.

Can the ADFS7124-8BBCPZ operate with both internal and external references?

Yes, the ADFS7124-8BBCPZ accepts either its internal 2.5 V band gap reference (15 ppm/°C drift, 70 µA quiescent) or an external differential reference applied to REFIN+ and REFIN−. The internal reference can be buffered to drive external circuits, and the external reference path supports voltages from 0.5 V to AVDD with ±0.2% initial accuracy. Reference selection is controlled via the REF_SEL bit in the ADC_CONTROL register.

What are the power supply requirements for the ADFS7124-8BBCPZ analog and digital sections?

The ADFS7124-8BBCPZ requires separate analog and digital supplies: AVDD/AVSS must be 2.7–3.6 V (low/mid power) or 2.9–3.6 V (full power), with AVSS optionally at −1.8 V for bipolar operation; IOVDD must be 1.65–3.6 V. This dual-supply architecture isolates noise-sensitive analog circuitry from digital switching, and the ADFS7124-8BBCPZ includes independent ALDO and DLDO regulators to maintain stability across load transients.