Issue link: https://resources.mouser.com/i/1442793
19 cable. LED lighting networks PoE system architecture includes the following devices, discussed in the next sections: - PoE gateways - LED light fixtures - LED lights - LED smart drivers - LED cable harnesses - Sensors - Wireless switches and dimmers PoE Gateways While computers and network interfaces control the management layer of the PoE network, the start of an integrated LED lighting system relies greatly on the device layer and the level of system components used to make the network. A PoE gateway is the device at the heart of the system. These gateways connect to, control, and power the light fixture luminaries that operate the LEDs. They can control LED lighting functions, including dimming, color tuning, and sensor reporting. These gateways are capable of delivering up to 60W. In cases where more wattage is needed, such as in high bay lighting, AC line voltage (120VAC–277VAC) is still required, wherein a wireless line voltage relay can control the devices. In the IP industry, the standards derived from the Advanced Telecommunications Computing Architecture (ATCA or AdvancedTCA) call out for 48VDC. Because of this standard, it is natural to provide PoE gateways that are configured to one of the following configurations: - Unregulated 48VDC - Constant voltage 24VDC/48VDC - Constant current Wireless PoE gateways that conform to IEEE 802 standards may also be used. They run at standard frequencies (902MHz, North America; 868MHz, Europe). Commonly, they have an effective range of about 15m. They enable secure two-way communication for control status of multiple wireless devices without designers needing to have cause for concern with interference happening with other devices. Silicon Labs is a leading provider of silicon, software, and solutions for a smarter, more connected world. Their award- winning technologies are shaping the future of IoT and helping to ensure connectivity in building and home automation. One way they are doing this is by providing the industry's most highly-integrated PoE devices. Their high-efficiency feature-rich products target smart lighting, IP cameras, wireless access points, and IP phones. The Silicon Labs Si3404 Power over Ethernet (PoE) Device is an IEEE 802.3 Type 1-compliant, 15W PoE power device (PD) interface and pulse-width-modulated (PWM) switching regulator Figure 1. By setting a new bar for device integration, lowest overall BOM cost, efficiency, and reliability, the Si3404 enables designers to add PoE functionality to their Ethernet products. When included in the design of a PoE-enabled system the Si3404 converts the high voltage (often ±48VDC) supplied over Ethernet copper unshielded twisted pair (UTP) cabling into a regulated, low-voltage DC supply. Also, the Si3404 combines all the required IEEE 802.3 detection, classification and hot-swap interfaces with a complete, high efficiency, PWM switching regulator. Simply add input diode bridges to achieve a best-in-class integration-to-area ratio PoE PD solution. PoE+ technology provides 30W of power to support more demanding application tasks. Silicon Labs' Si3406 Power over Ethernet Plus (PoE+) Device family is the ideal powered device interface solution for PoE+-enabled IoT products in building and home automation environments. The Si3406 regulator's switching frequency is tunable with a simple external resistor value to avoid unwanted harmonics. An integrated synchronous driver can control a secondary side field effect transistor (FET) to improve power conversion efficiency. The family's current-mode-controlled switching regulator supports multiple isolated and non-isolated power supply topologies. An integrated power switching FET complements the regulator. This flexibility, along with Silicon Labs' comprehensive PoE PD reference designs, makes it easier for developers to deploy critical power supply subsystems. LED Light Fixtures The LED light fixture itself is a critical and enabling component of the system. At its core, the fixture relies on the selection of the specific illuminating LED itself. In LED lighting systems that are not intelligently connected and networked, the LEDs used are substituted for traditional lights. The inherent superior technological efficiencies of LEDs relative to incandescent or fluorescent lights provide the efficiency benefits. However, connected intelligent lighting systems ratchet the whole system Figure 1: Silicon Labs' Si3404 Power over Ethernet (PoE) Powered Device (PD) is a highly-integrated, IEEE 802.3at Type 1-compliant, Pulse-Width-Modulated (PWM) Switching Regulator. (Source: Mouser Electronics)