Speed Up Compact Design of Fully Software Configurable Analog Input Modules Using NAFE13388-UIM

NXP’s N-AFE analog front-end family of devices for factory automation enables the software-defined factory. With its software-configurable analog inputs, where each input can be configured for voltage, current, temperature or resistance, NXP’s N-AFE enables a new level of flexibility.

With NXP’s N-AFE, enhanced accuracy and precision in manufacturing floor measurement, product quality is greatly improved. NXP’s N-AFE advanced diagnostics and anomaly detection features enable predictive maintenance, making it possible to identify issues before they occur to avoid downtime. All these features and more allow manufacturers to create a highly efficient smart factory.

The NAFE13388-UIM board enables quick evaluation of these NXP analog front ends. This board interfaces with the FRDM-MCXN947 board using the Arduino compatible connectors. The FRDM-MCXN947 is a compact and scalable development board for rapid prototyping of the MCX N94 or N54 MCUs. This NAFE13388-UIM and FRDM-MCXN947 solution is unique as it illustrates a compact system design of analog input modules. It speeds up your system design with readily available MCUXpresso SDK drivers and a GUI for evaluation.

The NAFE13388-UIM board is a compact design, measuring only 9cm by 5cm. It’s an EMC-compliant and fully tested hardware solution, so engineers can quickly adopt this design. It consists of NAFE13388, tested power supply circuits to generate NAFE’s voltage supply (+/-15V, 3.3V), digital isolators to protect the MCU from any kind of analog signals, and switches to leverage the software configurability of NAFE13388. All the necessary signals are routed to Arduino headers.

NAFE13388-UIM and FRDM-MCXN947 make it feasible to develop such a small analog input module. In addition to 24-bit sigma-delta ADC with digital filters, NAFE incorporates high voltage, low-leakage multiplexer (up to ±25 V), a PGA with high CMRR (90 dB) and high input impedance (1 G?), and integrated voltage/current excitation circuitry. NAFE saves PCB area by eliminating the need for external components, which are typically large and costly.

The accuracy (0.002% after user calibration) and precision (24-bit ENOB up to 30sps) requirements have been fully tested for this small design. The 180 dB dynamic range of the NAFE13388 allows for 2 uVRMS noise and 10V input voltage measurement.

Not limiting itself to only hardware flexibility, the NAFE13388-UIM solution brings MCUXpresso SDK drivers and reference applications to speed up your software development. MCUXpresso includes all the tools necessary to develop high-quality embedded software applications. All the codes with detailed instruction guides are available at the application code hub (ACH).

This codebase provides six applications of NAFE13388-UIM to test the different reading modes provided for ADC. MCUXpresso SDK allows creating customized code by leveraging the software configurability of NAFE13388. Users can change various parameters such as ADC data rate, SINC filters, setting modes, channel programmable delay, etc.

The NAFE13388-UIM solution has a graphical user interface (GUI) that allows users to configure NAFE13388 and execute several applications, including load cell, voltage, current and RTD (temperature sensing), for additional quick evaluation. A graphical user interface (GUI) facilitates the rapid evaluation of various sensors and the experimentation with configuration parameters to attain optimal performance.

Overall, the complete NAFE13388-UIM and FRDM-MCXN 947 solution will definitely speed up the hardware and software development of fully software-configurable analog input modules.

Author | Madhura Tapse

Madhura Tapse joined NXP Semiconductors as Product Marketing Manager in 2023 and has worked on various products that cater to industry 4.0 or industrial automation applications. Prior to joining NXP, Tapse worked as an applications engineer at Maxim Integrated (Now, Analog Devices) and at Cypress Semiconductors. She holds a Bachelor of Science degree in Electrical Engineering from Pune University and master’s degree in Biomedical engineering from Indian Institute of Technology, Bombay.