* *Reviewer:* @ngu25
* *Full Review and Getting Started Guide:* https://www.devheads.io/wp-content/uploads/2024/04/X_NUCLEO_LPM01A_DevHeads_Review.pdf

The [X-NUCLEO-LPM01A kit](https://www.st.com/en/evaluation-tools/x-nucleo-lpm01a.html) by STMicroelectronics is a power monitoring board with a programmable power supply. Its key features include:

● Works as an adjustable power supply and current measurement device.
● Dynamic current measurement from 100nA to 50mA (180nW to 165mW power)
● Static current measurement from 1nA to 200mA along with energy measurement.
● Onboard LCD for quick visual monitoring as well as GUI software support.
● Adaptability to a variety of ST boards through Arduino Uno, Arduino Nano and basic 4-pin connectors.

These features are enabled by 3 x 12-bit ADC working at 5 Msamples/s with
STM32L496VGT6 target MCU running the STM32-LPM01-XN firmware preloaded in the board. These led me to go hands-on with this kit and share a review about. This review starts with a feature overview and getting started, then on looking at the adaptability with a plethora of board types, and further I’ve explored power measurement instances using LPBAM features on the STM32U5 device.

# Key Features
## 1. Static and Dynamic Measurements
Static current measurement involves measuring the average or constant current flow in a circuit over time. It is typically used to determine the steady-state power consumption or current draw of a device under normal operating conditions and gives an idea of how much power the device consumes when it is in a stable state. LPM01A device supports a stable current to be measured from 1 nA to 200 mA, with an accuracy of better than 2%.

While this current is rapidly changing or fluctuating in a circuit, dynamic measurement technique is to be used. It helps to analyse the transient behavior, switching characteristics of a circuit, especially in applications having variable power demands. This device allows measurement of fluctuating currents from 100 nA to 50 mA with an accuracy in the range of 2%. This feature is made possible through ADCs working at 3.2 Megasamples/s.

The measurement mode can be selected by left navigation in the joystick.

## 2. Flexible Input and Output Power Supply
LPM01A has an adjustable voltage source that can power supply a target board from 1.8V to 3.3V and measure its current consumption at the same time.

This option as well can be selected from the same left navigation in the joystick.

The board can be powered in multiple ways including USB host port, USB charger, an external DC supply(10V maximum) and also through the Arduino UNO or Nano connectors.

## 3. Adapting to Nucleo-64 and Using Basic Connectors
The board adapts through its Arduino UNO connectors for Nucleo-64 type boards right away. With the LPM01A board jumper settings, the target MCU can be powered from the AREF pin of the Arduino connector. This allows the MCU supply to be isolated from other peripherals like ST-LINK in order to measure the MCU power consumption only.

## 4. Interface with STCubePowerMonitor tool
Along with the onboard LCD display, LPM01A can function in Host-Controlled mode with a PC. The board can simply be interfaced with a USB cable and running the STM32CubePowerMonitor tool along with VCP drivers installed, we’re good to go. Also to note is that the manual control through the joystick is disabled while on Host-Controlled mode.

> **Issue:** The X-NUCLEO-LPM01A board comes with Firmware Version 1.0.1 loaded and this does not work with the latest version of STM32CubePowerMonitor tool(Version 1.2.1). There is an error message regarding ‘inability to establish serial communication’ popping up every time I choose the COM port and click on the Start Acquisition button. I had to switch back to Version 1.1.1 over which the board worked fluently.

# Next: [Unboxing & Getting Started](https://www.devheads.io/wp-content/uploads/2024/04/X_NUCLEO_LPM01A_DevHeads_Review.pdf)