藍牙4.1，4.2和5兼容的藍牙低功耗SoC和工具滿足物聯網的挑戰

　　藍牙低能量通過版本4.1，4.2和5的顯著升級的目的是使短距離無線標準的物聯網（物聯網）無線應用的更好選擇。這兩部分組成的系列的第1部分介紹了這些升級和概述他們的優勢。2部分，在這里，介紹了低功耗藍牙SoCs，模塊和工具，并討論了它們的相對平衡作為一種設計方法。在該系列的結束，一個稱職的設計師應該舒適開始藍牙低能耗設計。

　　雖然一些芯片廠商現在提供低功耗藍牙收發器片上系統（SoC），符合標準的最新版本，以利用所有的新功能是很棘手的。如果從空白表開始，開發人員必須應付相對復雜的RF外圍電路設計，然后編寫應用軟件，優化他們的應用程序，但接口順利與制造商的測試和驗證藍牙低能量協議軟件（“堆棧”）。然后，他們必須獲得監管符合他們的無線樣機。選擇一個模塊可以通過消除外圍電路的設計和合規性測試的過程，但這可以增加成本和解決方案的足跡。

Figure 1: Bluetooth low energy chipmakers generally take a highly integrated SoC approach. The solutions require few peripheral components and use ARM Cortex-M[x] processors to run both the stack and application code. The schematic shows Cypress Semiconductor’s CYBL1xx7x Bluetooth low energy SoC. (Image source: Cypress Semiconductor)

Chief among these subsystems is the CPU subsystem, typically comprising an embedded ARM processor and memory blocks. A direct memory access (DMA) controller enables certain operations to take place without using MCU resources. The embedded ARM core brings many advantages. These include wide adoption, a strong ecosystem, and the support of several popular integrated design environments (IDEs). The core has been specifically designed for low-power consumption and the device has sufficient computational overhead to concurrently run the stack and sophisticated application code. This eliminates the complexity, cost and space requirements of a separate application processor.