STM32W108B-SK STMicroelectronics, STM32W108B-SK Datasheet
STM32W108B-SK
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STM32W108B-SK Summary of contents
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... PCB design guidelines for the STM32W108 platform 1 Introduction STMicroelectronics provides a IEEE 802.15.4 product design engineer with a number of paths towards the successful design of a IEEE 802.15.4-compliant solution based on the STMicroelectronics STM32W108 family of system-on-chip (SoC) platforms. The STM32W108xx kits contain software, hardware, and documentation designed for developers to create applications efficiently on a tested and controlled platform ...
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Contents Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...
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AN3206 2 Reference design Figure 1 shows a block diagram of the reference design. Figure 1. Block diagram of STM32W108 reference design (48-pin package) The STM32W108 reference design uses an external 50/100 Balun as its primary RF component. It provides ...
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Reference design 2.1 RF design guidelines 2.1.1 STM32W108 RF ports The STM32W108's bi-directional RF port (pins RF_P and RF_N) provides access to a low noise amplifier (LNA) and a power amplifier (PA) through a shared differential interface. The disabled high-Z ...
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AN3206 would yield higher signal voltage swings at the LNA input, making the input referred noise less significant and thereby improving sensitivity. However, this also increases the source resistance, thereby increasing the source noise voltage. In practice at the 700Ω ...
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Reference design To minimize network loss, the matching topology should try to keep Smith chart loci towards the center of the Smith chart that, the following impedance transformation options are available: ● Series inductance followed by Shunt capacitance ...
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AN3206 Figure 3. STM32W Ceramic Balun matching network Figure 4 shows a PCB layout (layer 1 important that the PCB designer notice the routes between the STM32W and the balun. ST recommends the use of an 0603 inductor ...
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Reference design By routing in this manner, PCB area and cost are wasted. It also requires the model to be updated to a three-element match, generally making it more difficult to simulate. An added benefit of using an 0603 inductor ...
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AN3206 using a vector network analyzer (VNA easy to figure out with the help of a Smith chart the value needed to compensate the de-adaptation. In our practical case, a serial capacitor (C8) and inductor (L1) have been ...
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Non-RF design considerations 3 Non-RF design considerations To operate properly, each STM32W Reference design contains additional, non-RF components. These include a 24-MHz crystal, appropriate decoupling capacitors and RF test point as well as an InSight Port connector. 3.1 High-frequency (24-MHz) ...
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AN3206 Table 2. High frequency crystal requirements Parameter Frequency Duty cycle Phase noise from 1kHz to 100kHz Accuracy Crystal ESR Crystal ESR Start-up time to stable clock (max. bias) Start-up time to stable clock (optimum bias) 3.2 Optional Low-frequency crystal ...
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Non-RF design considerations 3.3 1.8V regulator load capacitor The STM32W operates over a supply voltage (V regulator converts V 2.2 µF ceramic loading capacitor is required on the output of VREG_OUT of the STM32W. A series resistor (R5) is used ...
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... To assist with manufacturing testing of the printed circuit assemblies, ST recommends having the possibility to solder an UF.L type RF connector such as those from Hirose. After reading this document If you have questions or require assistance with the procedures described in this document, please contact STMicroelectronics support at http://www.st.com/stm32w. 4 Revision history Table 3. ...
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... Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...