Building on the 2024 MCX portfolio launch momentum, NXP is announcing the MCX L series of ultra-low-power MCUs. MCX L uses many of the same peripherals as the current MCX portfolio but is distinguished by a novel power management architecture that supports always-on, battery-powered applications.
Looking Forward to the Lower Power Future with MCX L Series
MCX L represents decades of lower power design experience. Combining this experience with an advanced 40 nm Ultra Low Power (ULP) semiconductor process, we created a new IP known as Adaptive Dynamic Voltage Control (ADVC) for use in the MCX L series. The ADVC subsystem enables truly remarkable performance for energy-constrained applications, whether they are powered by a battery, ultracapacitor or power harvesting circuit.
Low Power by Design
MCX L provides a dual-domain architecture merging real-time processing and ultra-low-power sensing functions into a single device. The MCX L processing architecture is composed of an Arm® Cortex®-M33 real-time domain and an Arm Cortex-M0+ ULP always-on sense domain.
MCX L25x Block Diagram.
To better experience, download the block diagram.
The M33 core in the real-time domain runs up to 96 MHz with a 24 µA/MHz current consumption characteristic.
The real-time core implements the Armv8-M Baseline ISA with SIMD DSP instructions and a floating-point unit. This enables fast and efficient on-demand processing of data acquired by the ULP domain for transmission over a wired/wireless network or logging to a storage mechanism.
The MCX L series will be featured in a Building Automation demo at CES. Visit NXP at CES 2025 booth CP 107.
The M0+ core is intended for always-on operation to collect sensor data using a combination of the low-power analog and digital peripherals in the always-on domain. As an example, the ULP sense subsystem consumes only 14 µA running at 2 MHz while performing a 100 kbit/s I²C transaction. There are seven low-power modes, enabling sub-µA power consumption in the deepest sleep modes. For example, the MCX L can achieve 650 nA with button wake-up or 700 nA with autonomous wake-up.
The power management functions are integral to the MCX L system design and the exceptional performance is enabled by the ADVC IP.
AVDC is Integrated into the System Power Management Architecture
The device core voltage, typically 0.9 V for a 40 nm ULP process, is dynamically tuned by the AVDC. The ADVC will adjust the system operation point to ensure the core supply Vop is running as close as possible to the internal transistor threshold voltage Vt. Power consumption scales with the operating voltage as ∆Vop².
Reducing the operating point to the smallest possible value ensures the lowest dynamic power consumption. Because of the squared scaling law, small changes in operating voltage can have a large effect on power consumption. For example, reducing the operating voltage from 0.9 V to 0.65 V reduces power consumption by half in the MCX L.
ADVC tunes the operating point for environmental conditions such as process, temperature and aging. Embedded developers can take advantage of this technology with minimal domain knowledge as the ADVC and power management modes are controlled via a simple SDK API.
Lower Power Peripherals for a Variety of Applications
The MCX L14 and L25 peripherals are split between the real-time and ULP always-on domain. Each peripheral set for each part was designed to balance performance, integration and cost for different application requirements.
The L25 family brings key features for industrial process control and flow metering applications. The combination of the SLCD to drive lower power LCDs combined with the low-power I²C/UARTs and the keypad peripheral running in ULP sense domain means that developers can have an agile platform for creating families of metering products. The lower power analog and timer peripherals enable flexibility in the approach used for the underlying sensing technology. The MCX L25 enables meters that can use all the common measurement topologies such as passive inductive/capacitive, paddle, different pressure and ultrasonic sensing.
Industrial Flow Metering.
The dual-domain MCX L architecture enables a separation of concerns between the high-level metering application/user interface and the underlying metrology/data acquisition. This enables a large degree of agility in how designers approach their own product families.
For deeply embedded industrial and commercial sensing applications, the MCX L14 provides key features to meet cost, power, local compute and packaging requirements. The L14 has much of the same capability in terms of ADC, timers and connectivity but excludes the HMI capabilities for deeply embedded sensing and control applications.
Industrial applications for the MCX L14 include smart temperature, gas, pressure or contact sensors. Standard UART interfaces make it easy to design with industrial protocols such as MODBUS. For residential and build/infrastructure applications, the L14 could be used for battery-powered air quality, motion, fire/smoke, lighting or water-leak sensors.
Secure By Design with NXP EdgeLock® Security
MCX L security integrates an array of hardware tools to implement a robust security framework. NXP EdgeLock Security can support the security needs of a wide variety of industrial, building/infrastructure and residential applications.
The MCX L ROM includes tools for implementing secure provisioning workflows. This includes secure bootloader features built into ROM, cryptographic accelerators to accelerator encryption and signature checking, a true random generator, physical/logical TrustZone software isolation, device life cycle management with One Time Programmable (OTP) fuses and built-in security key.
These security features and MCUXpresso security tools help developers meet current and upcoming compliance requirements. Cyber security regulations are starting to be enforced to ensure a minimal level of security for IoT devices. The EU Cyber Resilience Act (CRA) launches in 2025 with full enforcement in 2027 to get CE Mark. The US CTM (NIST 8425) launched in 2024 which is voluntary for now but may become required in the future.
MCUXpresso Developer Experience
At the heart of the MCX portfolio is the MCUXpresso Developer Experience. MCUXpresso offers core software development kits (SDKs), Integrated Development Environments (IDEs) and configuration tooling. The SDK for MCX L includes low-level peripheral drivers, configuration utilities and wireless protocol enablement.
MCX L is well suited for bare metal applications but is RTOS capable. FreeRTOS samples will be available in the SDK with support for Zephyr in the future.
As part of the MCUXpresso Developer Experience, NXP offers low-cost FRDM development boards. These boards include an onboard programmer/debugger and offer rapid prototyping through the Arduino® and mikroBUS headers, with add-on boards available through the Expansion Board Hub .
FRDM Development Boards.
Another development resource that dovetails with the MCX L SDK and expansion board hub is the Application Code Hub (ACH). The ACH repository has high-level software examples, code snippets and demos. These examples pair with the SDK and can be directly accessed from within into MCUXpresso IDE or via the ACH web interface .
The MCX L will initially be available in two devices package for hardware designs:
- LQFP100 14 x 14 x 1.4 mm, 0.5 mm pitch
- VFBGA184 9 x 9 x 1 mm, 0.5 mm pitch
Longer term availability is crucial for industrial applications and the MCX L series will be part of the NXP Product Longevity program.
Wrapping Up and Looking Forward
The MCX L14 and L25 are the newest members of the MCX portfolio. MCX L is focused on ultra-low-power, always-on applications and can achieve best-in-class power characteristics via NXP’s proprietary ADVC technology. The new MCX L dual-core architecture uses three times less power than previous MCX devices, and extends the battery life for smart sensor nodes, flow meters and other battery-constrained industrial and IoT devices.
