NXP Semiconductors RD-UAMP-SENSOR

Overview

RD-UAMP-SENSOR from NXP Semiconductors is a Cortex-M4-based current measurement shield designed to interpose between an Arduino-compatible MCU board and its peripheral shield, enabling non-intrusive, high-precision current acquisition across two independent channels (SHLD and MCU). It supports 60 nA–5 mA measurement range, automatic/manual range switching via four shunt resistors per channel, and on-board 3.3 V precision voltage reference for low-current accuracy.

For engineers reviewing the RD-UAMP-SENSOR datasheet, RD-UAMP-SENSOR pinout, RD-UAMP-SENSOR application, or RD-UAMP-SENSOR equivalent, this page delivers verified technical context, I²C register-level interface details, configurable acquisition parameters, offset calibration workflow, and Freedom Sensor Toolbox integration guidance - all specific to the production-ready reference design board.

Technical Context

The RD-UAMP-SENSOR implements dual independent current measurement units: one for shield-side (SHLD) current and one for MCU-side current, each using four selectable shunt resistors and a fixed-gain (G = 25) amplifier. Each unit integrates optional low/med/high filtering (100 nF / 1 µF / 10 µF) and uses a dedicated 3.3 V high-precision voltage reference for SHLD measurements.

Firmware executes a multi-stage acquisition pipeline: eDMA captures 100-sample buffers from a 16-bit ADC; hardware averaging reduces noise (8-sample); firmware computes running avg/min/max over user-configurable time windows (100 ms to 3 s), with DRDY flagging new data readiness and DOWR indicating buffer overwrite.

Key Specifications

Availability

RD-UAMP-SENSOR is available at Aetrix Electronics and suitable for current profiling, ultra-low-power validation, embedded power optimization, and sensor subsystem characterization requiring stable component supply and repeatable metrology-grade measurement.

Supply support for RD-UAMP-SENSOR 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

NXP Semiconductors is a global semiconductor company specializing in secure connectivity solutions for automotive, industrial, IoT, and mobile applications, with deep expertise in ARM-based microcontrollers and sensor ecosystem tooling.

The RD-UAMP-SENSOR belongs to NXP's Freedom Development Ecosystem reference design family, engineered specifically to accelerate current consumption analysis and power-aware firmware development for Cortex-M4-based platforms.

FAQ

What is the primary function of the RD-UAMP-SENSOR?

The RD-UAMP-SENSOR is a current measurement shield that enables precise, non-intrusive acquisition of both shield-side (SHLD) and MCU-side current draw. It operates by inserting between an Arduino-compatible MCU board and its peripheral shield, routing all signals except 3.3 V through dual measurement units-each with four shunt resistors, gain-of-25 amplification, and configurable filtering. The RD-UAMP-SENSOR delivers real-time avg/min/max current values over user-defined acquisition windows, supporting firmware optimization and ultra-low-power validation workflows.

How does the RD-UAMP-SENSOR achieve its 60 nA–5 mA measurement range?

The RD-UAMP-SENSOR achieves its wide dynamic range using two independent current measurement units, each equipped with four discrete shunt resistors (supporting ranges: 40 µA, 200 µA, 1 mA, and 5 mA) and a fixed-gain (G = 25) amplifier. Range selection is controlled via the RC_BANK_SHLD and RC_BANK_MCU registers, while optional 100 nF / 1 µF / 10 µF filtering capacitors reduce noise for different current profiles. The SHLD unit further leverages a dedicated 3.3 V high-precision voltage reference to maintain accuracy at sub-microamp levels - a key enabler of the 60 nA lower bound in the RD-UAMP-SENSOR specification.

Can the RD-UAMP-SENSOR be used without an NXP Freedom board?

Yes, the RD-UAMP-SENSOR is explicitly designed for non-intrusive interfacing with any 3.3 V Arduino-like development board-not only NXP Freedom kits. Its physical layout and pin mapping mirror standard Arduino Uno R3 headers, allowing direct stacking. Power for MCU current measurement requires onboard USB or battery supply (not external 5 V), but SHLD current measurement functions regardless of MCU power source. All communication interfaces-including LCD menu, I²C sensor emulation (0x0E), serial protocol, and optional Bluetooth-are fully accessible and documented for third-party MCU integration in the RD-UAMP-SENSOR user manual (UM11470).

What calibration capabilities does the RD-UAMP-SENSOR provide?

The RD-UAMP-SENSOR implements per-shunt offset calibration for all eight resistors (four per channel), storing float-format correction values in non-volatile memory. Calibration eliminates constant residual bias errors and persists across factory resets. It runs automatically at first boot or can be triggered manually via I²C (CTRL_REG2.CALIB = 1) or LCD menu. Unlike internal ADC calibration (performed on every boot), offset calibration is environment-aware and accounts for external circuit effects. The RD-UAMP-SENSOR user manual confirms that calibration values remain valid until explicitly re-run, ensuring long-term repeatability without recalibration during routine use.

How does the RD-UAMP-SENSOR communicate measurement data?

The RD-UAMP-SENSOR provides four concurrent communication paths: (1) LCD module with capacitive buttons for live visualization and menu-driven configuration; (2) I²C interface (address 0x0E) with a full register map emulating NXP sensors - including WHO_AM_I = 0xC4, status flags (DRDY/DOWR), and float-format avg/min/max registers (IDD_AVG_FLT1–4); (3) UART/USB serial port using a custom ASCII protocol; and (4) optional Bluetooth module. All interfaces expose identical acquisition parameters and calibrated measurement results, enabling flexible integration into test automation, GUI tools, or Freedom Sensor Toolbox (CE) without hardware modification to the RD-UAMP-SENSOR board.