藍(lán)牙4.1，4.2和5兼容的藍(lán)牙低功耗SoC和工具滿足物聯(lián)網(wǎng)的挑戰(zhàn)

　　藍(lán)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(biāo)準(zhǔn)的物聯(lián)網(wǎng)（物聯(lián)網(wǎng)）無線應(yīng)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(yōu)勢。2部分，在這里，介紹了低功耗藍(lán)牙SoCs，模塊和工具，并討論了它們的相對平衡作為一種設(shè)計方法。在該系列的結(jié)束，一個稱職的設(shè)計師應(yīng)該舒適開始藍(lán)牙低能耗設(shè)計。

　　雖然一些芯片廠商現(xiàn)在提供低功耗藍(lán)牙收發(fā)器片上系統(tǒng)（SoC），符合標(biāo)準(zhǔn)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(fā)人員必須應(yīng)付相對復(fù)雜的RF外圍電路設(shè)計，然后編寫應(yīng)用軟件，優(yōu)化他們的應(yīng)用程序，但接口順利與制造商的測試和驗證藍(lán)牙低能量協(xié)議軟件（“堆棧”）。然后，他們必須獲得監(jiān)管符合他們的無線樣機(jī)。選擇一個模塊可以通過消除外圍電路的設(shè)計和合規(guī)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.