NXP LPC3240+JN5168智能家居网关方案

图4。IOT网关系统框图

完整的网关系统包括：

Routers

The IP routers, provide Internet Protocol routing services for devices in the network. This provides standard IP routing of packets in the LAN and WAN domains via standard internet router devices.
Commands from devices in the LAN or WAN can be passed into the WPAN via the JenNet-IP gateway using cabled Ethernet connections or Wi-Fi links as shown by the solid and dotted grey lines in the LAN and WAN domains of the gateway system topology diagram.

Gateway

Adding a JenNet-IP gateway device to the internet router extends the IP network into the WPAN domain providing low power wireless access to the Smart Device network. The JenNet-IP gateway includes a border router device, (either internally or externally), which provides the WPAN radio services.
Commands sent to individual devices in the WPAN follow the tree structure of the JenNet-IP network, (represented by the dotted grey lines in the WPAN domain of the gateway system topology diagram).

Commands broadcast to groups of devices are simply broadcast to every device in range of the original transmission, receiving devices then re-broadcast the commands ensuring that they reach every device in the network. Only the devices that are members of the group the command is addressed to will take any action (such as turning on a bulb) upon receipt of a group broadcast (though all devices re-broadcast to ensure the command reaches all devices in the network).

Smart Devices

Bulbs: allow wireless control of lighting in the home. These devices act as router nodes in the low power JenNet-IP wireless network extending the network for other Smart Devices to join.

Sensors: monitor occupancy and light levels in an area and can control the bulbs based upon their readings.

Remote controls: allow control of other Smart Devices in the low power JenNet-IP wireless network. These devices operate as sleeping broadcaster devices in order to allow mobile operation and preserve battery life. To do this they spend most of their time asleep, thus preserving power, only waking to read button inputs. Commands are always broadcast to a group of devices so the remote control does not need to maintain a full connection to the network. This allows the remote control to be freely moved around the area covered by the WPAN.

AC-DC开关电源属于A级ITE还是B级ITE? 如题。
沙发

阻焊显影阻焊显影步骤同线路显影。

关于张占松老师《电源设计一书》中的疑惑？


这是正激变压器的Ap法设计公式，感觉怎么算都不对呢？式中的5.4怎么来的？


为什么我算出来就是0.361？
書本供參考，不一定全對

大电流电感

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