Overview
Tools & Software
Resources
Solutions
Quality & Reliability
Sales Briefcase
eDesignSuite
Get Started
Sample & Buy
Partner products
  • The X-CUBE-CLKTRIM Expansion Package illustrates the trimming of an HSE crystal oscillator in order to reach the high-accuracy frequency required by RF applications.

    The STM32WB Series microcontrollers support low-power RF standards such as Bluetooth® Low Energy and IEEE 802.15.4. Bluetooth® Low Energy requires a minimum ±20 ppm RF clock accuracy while IEEE 802.15.4 accuracy requirement is ±40 ppm.
    The STM32WL Series microcontrollers support sub-GHz RF standards such as LoRaWAN® and meet the requirements of a wide range of wireless applications for low-power wide area networks (LPWAN). For LoRaWAN® as well as for other LPWAN applications, the highest the RF clock accuracy, the best the RF performance.
    STM32WB Series and STM32WL Series offer an efficient architecture with internal load capacitors that allow the fine tuning of the crystal frequency (32 MHz), saving the extra cost of additional external capacitors. Internal capacitance values are register controlled. They depend on various factors such as process variation, crystal, and PCB design and must therefore be set for each device individually.
    The X-CUBE-CLKTRIM Expansion Package proposes three different trimming procedures (manual, automatic, and with STM32CubeMonitor-RF (STM32CubeMonRF)) that allow the once-for-all storage of the right capacitance values in OTP bytes. Each proposes two configurations: the trimming procedure itself and an implementation example of HSE clock initialization in RF applications.
    The manual trimming procedure consists in measuring the RF clock with a precision frequency meter (better than 0.1 ppm). The RF clock frequency value is controlled through the user push-buttons so that the best clock accuracy can be calibrated step by step.
    The automatic trimming procedure consists in providing a precision clock reference to the STM32 so that it can trim its RF clock frequency itself, without any user intervention needed.
    The STM32CubeMonitor-RF trimming procedure consists in measuring the RF clock with a precision frequency meter (better than 0.1 ppm). The RF clock frequency value is controlled by means of STM32CubeMonitor-RF configurable scripts for calibrating the best clock accuracy step by step.
    X-CUBE-CLKTRIM firmware is built on the HAL drivers and runs on the Nucleo boards of the STM32 Wireless MCUs (STM32WB Series only).

    Key Features

    • High-speed external (HSE) crystal oscillator trimming
    • Allows best RF performance for Bluetooth® Low Energy, IEEE 802.15.4, LoRaWAN® and LPWAN wireless applications
    • Trimming parameters stored in user OTP Flash area

Get Software

Recommended for you

Latest from ST

Embedded Software

    • Part Number

      STM32Cube MCU Package for STM32WB series (HAL and LL low level drivers, USB, File system, RTOS - coming with examples running on ST boards: STM32 Nucleo, Discovery kits and Evaluation boards)

Evaluation Tools

    • Part Number

      Bluetooth™ 5 and 802.15.4 Nucleo Pack including USB dongle and Nucleo-68 with STM32WB55 MCUs, supports Arduino™ Uno V3 and ST morpho connectivity

00 Files selected for download

Technical Documentation

    • Description Version Size Action
      DB3399
      HSE trimming for STM32 Wireless MCUs software expansion for STM32Cube
      2.0
      133.19 KB
      PDF
      DB3399

      HSE trimming for STM32 Wireless MCUs software expansion for STM32Cube

    • Description Version Size Action
      AN5042
      Precise HSE frequency trimming using STM32 wireless MCUs
      5.0
      1.14 MB
      PDF
      AN5042

      Precise HSE frequency trimming using STM32 wireless MCUs

    • Description Version Size Action
      UM2312
      Development checklist for STM32Cube Expansion Packages
      2.0
      306.99 KB
      PDF
      UM2285
      Development guidelines for STM32Cube Expansion Packages
      1.0
      485.46 KB
      PDF
      UM2312

      Development checklist for STM32Cube Expansion Packages

      UM2285

      Development guidelines for STM32Cube Expansion Packages

Presentations & Training Material

    • Description Version Size Action
      STM32 and STM8 embedded software solutions 7.0
      3.12 MB
      PDF

      STM32 and STM8 embedded software solutions

Publications and Collaterals

    • Description Version Size Action
      STM32 Open Development Environment Brochure 17.09
      1.21 MB
      PDF
      Sensor & motion algorithm software pack for STM32Cube 1.0
      544.58 KB
      PDF

      STM32 Open Development Environment Brochure

      Sensor & motion algorithm software pack for STM32Cube

Legal

    • Description Version Size Action
      SLA0048
      Mix Ultimate Liberty+OSS+3rd-party V1 - SOFTWARE LICENSE AGREEMENT
      6.3
      87.58 KB
      PDF
      SLA0048

      Mix Ultimate Liberty+OSS+3rd-party V1 - SOFTWARE LICENSE AGREEMENT

Support & Feedback

Let us help you!