Smart lighting: A bright idea whose time has come Rev. 1 20 December 2011 Report Document information Info Keywords Abstract Content UBA2015A, UBA2016A, UBA20270T, UBA20271T, UBA20272T, TEA1721BT, TEA1721AT, TEA1721DT, TEA1731, TEA1733, SSL2101T, SSL2102T, SSL2103T, SSL21081, SSL21082, SSL21083, SSL21084, SSL2109, SSL4101, JN5142, JN5148, Smart lighting, IP connectivity Smart lighting brings together wireless IP connectivity, energy-efficient lighting, and low-power standby (down to 50 mw), in a compact, low-cost solution that enables new ways to control lights and manage energy conservation.
Revision history Rev Date Description v.1 20111220 first issue Contact information For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 2 of 10
1. Introduction The increasing cost of energy, concerns about global warming due to CO2 emissions, and, more recently, supply issues resulting from natural disasters, such as the earthquake in Japan, are driving energy-reduction programs. Lighting, which represents up to 25 % of home energy usage, is a natural place to start when looking for ways to save on energy. The transition to newer, more efficient lighting technologies has already begun to replace incandescent bulbs. Compact-fluorescent lighting (CFL) and Solid-State Lighting (SSL), two of the most popular alternatives to incandescent bulbs, are now commonplace in homes, offices, retail spaces, and along city streets and highways. A number of governments around the world have even passed measures to phase out incandescent bulbs entirely, so it is likely that CFLs and SSLs will continue to grow in popularity. The latest CFLs and SSLs are equipped with very compact, relatively inexpensive driver ICs that deliver even higher energy efficiency (more lumen light output per watt of energy input). The control circuitry adds a range of other benefits, including improved system reliability, boost functions that reduce start-up time, deep dimming capabilities, and extended lamp lifetimes (12,000 to 15,000 hours for CFL and over 35,000 hours for SSL). These next-generation CFLs and SSLs have already had a tangible impact on energy consumption, but there is more that can be done. Building on the concept of using driver ICs to improve lamp operations, there is a way to save even more. By adding wireless IP connectivity to the driver circuitry, it is possible to create a more intelligent light bulb. The new approach makes it easier to manage energy consumption, because individual lamps can be used only when and where they are needed, and at the right brightness level. Also, the wireless approach provides a simple way to implement a smart lighting network in existing residences, so even older homes can take advantage of the new concept. 2. An internet address for every bulb Figure 1 shows a home automation network that uses smart lighting. Fig 1. A smart lighting network Every lamp has its own IP address and can be wirelessly controlled by an IP device, such as a smartphone, tablet, laptop, or Internet-enabled TV. This makes it possible to create a highly personalized, intelligent lighting environment. Lights can turn on and off when and All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 3 of 10
where they are needed, at the desired level of brightness, while saving power and electricity costs. For example, consumers can define lighting scenarios that use different levels according to the task, such as dimmed lighting for watching a movie or bright lighting for reading a book. Lights can be programmed to turn off automatically at night, or to follow a predetermined on/off pattern when the inhabitant is away. Travelers can use their smartphones to control lights remotely, to ward off burglars and intruders. By adding IP-enabled sensors to the network, lights can be configured to operate autonomously, based on light levels or occupancy. Lights can turn on at dusk, when the amount of natural light starts to decrease, or they can automatically turn off when people leave the room. Smart lighting chipsets bring us one step closer to the Internet of things, a world in which appliances can be monitored and controlled via an IP address. As part of a building-management system, IP-enabled lights can provide self-diagnostic information to optimize maintenance schedules and reduce maintenance costs. For example, the lights can not only submit early failure reports but also track and report the number of burn hours or switching cycles. The consumer knows exactly when lamps are approaching end-of-life and can be replaced pre-emptively. As another example, system-level management of the lighting network gives utility companies a way to help consumers control their energy consumption remotely. Consumers may, for instance, choose to dim lights by 10 % during peak hours, when rates are higher. An existing internet connection and a control gateway to the home can control the light output. A 10 % decrease is likely to go unnoticed by the consumer, except on their energy bill. Utility companies can use options like these to educate consumers on how best to manage their energy consumption and reward their conservation efforts. All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 4 of 10
3. The GreenChip approach A new smart lighting chip set from NXP Semiconductors, called GreenChip, creates a wireless connection between the light bulb and a TCP/IP network. As shown in Figure 2, the GreenChip solution includes a CFL or SSL driver, a standby power supply, and hardware for wireless connectivity. Fig 2. The NXP GreenChip platform for smart lighting The dimmable SSL210x driver family, designed for SSL lamps, can provide up to 94 % energy efficiency. It works with a number of LED supply topologies, including isolated flyback, non-isolated buck-boost configurations, and antenna isolation as an option. The dimmable UBA2027x, for CFL lamps, is a combination driver and controller that addresses consumer complaints about CFLs. In particular, it provides deep dimming capabilities similar to those of incandescent lamps, includes a "boost" function that reduces the time from start-up to full light output, and extends lamp lifetimes to over 15,000 hours and up to 100,000 on/off switching cycles. The JN514x wireless IC is a low-power combination of an RF transceiver and a dedicated 32-bit RISC CPU. It operates at a frequency of 2.4 GHz. Because of its short wavelength, this frequency allows effective radiation from metal luminaires that usually surround the lamps. The effective range of the system is increased compared to sub-ghz alternatives. A software option on the JN514x provides capacitive touch key sensing functionality, enabling cap-touch remote controls without requiring any additional ICs. Table 1 shows an overview of the icfl and issl reference designs available to support the most common lamp types and supply topologies. Table 1. PWM dimming Analog dimming icfl and issl smart lighting reference designs CFL Non-isolated LEDs and antenna A19, BRx, PARx - SSL2108 buck; TEA1721; JN514x UBA2027x flyback; TEA1721; JN514x SSL2101 buck-boost; TEA1721; JN514x LED Isolated LEDs and Isolated LEDs and non-isolated antenna isolated antenna TLED, A19, BRx, PARx A19, BRx, PARx - - SSL2101 flyback; TEA1721; JN514x TEA1733 flyback; TEA1721; JN514x All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 5 of 10
Optional features: 110 V and 230 V Output power and standby power TRIAC compatibility Regional optimization of power factor ElectroMagnetic Interference (EMI) and harmonic regulation requirements Fast start-up time from mains power-on Open string protection (LED) The circuitry in the GreenChip platform is small enough to fit inside a standard light bulb. It can operate on the same wireless sensor network that may already be in place for energy metering, smart appliances or security systems (see Figure 3). Fig 3. NXP smart lighting module for 15 W SSL retrofit lamps The advantage of a wireless system over a wired one is that it enables a simple, low cost, and "aesthetically acceptable" installation, since there is no need for additional cabling. Using wireless also makes the system more flexible and more scalable, since it is easy to add new devices, such as lamps, switches or sensors. 3.1 Very low standby power The lamps spend much of their time in standby mode, waiting for commands. Commands can come from the user (for example, when someone toggles a wall switch or presses a button on a remote control) or from the network (for instance, when an occupancy sensor detects someone entering or exiting a room). The large amount of time spent waiting means that standby power consumption can be a serious issue. Consider an LED lamp that consumes 7 W of power when on and 0.5 W of power when in standby mode. We assume that, within a 24-hour period, the lamp is on for three hours and off, in standby mode, for 21 hours. In its on-state, the lamp consumes 21 watt-hours (7 W for 3 hours), and in its standby mode, it consumes 10.5 watt-hours (0.5 W for 21 hours). The conclusion is that the standby mode adds roughly 50 % to the lamp's daily energy usage, which is too much! All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 6 of 10
The GreenChip platform reduces power consumption, in active and standby modes, in several ways. First, the hardware for wireless connectivity is highly efficient. The JN5148 version, for example, consumes less than 17 ma when active. The sleep current of just 100 na supports coin battery lifetimes of more than 10 years. The IC can also be used with energy-harvesting switches, which make batteries unnecessary, and in remote controls with capacitive key sensing. The GreenChip solution includes a dedicated IC for standby power to minimize power consumption in standby mode. The TEA1721 is a buck converter that offers a no-load capacity of less than 10 mw. In standby mode, when configured with a standard ZigBee software stack, the entire GreenChip solution consumes roughly 140 mw. The standby power consumption can be reduced to below 50 mw by using a low-power routing option, in the JenNet-IP stack, that duty cycles the radio chip. Either way, the impact of standby power consumption is negligible in a network based on the GreenChip platform. 3.2 IP-based stack The GreenChip platform supports the use of any software stack based on IEEE 802.15.4, including ZigBee for the network layer. However, the full power-saving potential of the platform (that is, the standby power option of just 50 mw) and IP connectivity are only available with the JenNet-IP network stack, a 6LoWPAN mesh-under tree network, also based on IEEE 802.15.4, that specifically targets low-power operation in residential and industrial applications. Figure 4 shows a smart lighting network based on JenNet-IP. Fig 4. JenNet-IP based smart lighting network JenNet-IP commands are relayed from device to device using IPv6 packets. That means that, for example, a smartphone can communicate with a bulb without converting IP to ZigBee. There is no need for protocol conversion because the network provides end-to-end IP connectivity. This enhances network security and makes communications more reliable. It also reduces the cost of any gateways that tunnel commands from the Ethernet port of a router through an 802.15.4 radio into the wireless network. This is because the software required for the Ethernet-to-802.15.4 bridge can be implemented using the 32-bit microcontroller already embedded in the radio IC. There is no need for a separate, dedicated controller to manage the interaction between the Ethernet and 802.15.4 protocols. All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 7 of 10
Using JenNet-IP helps address many of the issues associated with traditional networks. It provides redundancy by using a self-healing mechanism that automatically finds a new route if the radio connection between two nodes is broken. It reshapes the network to minimize the number of hops, thus minimizing latency. On top of that it can be scaled to include hundreds of nodes. The JenNet-IP network can be controlled in a standalone mode, using a wireless (capacitive touch) remote control or wall switches. With the addition of a low-cost gateway, any IP-equipped device, such as a smartphone, tablet, PC or Internet-enabled TV can control the network. The gateway function also enables easy integration with commercial and industrial systems for building management. An option for over-the-network downloads provides a user-friendly environment for upgrading application code and firmware, so the solution can evolve over time. Running the JenNet-IP layer means that the GreenChip platform provides the lowest cost, lowest latency, and most widely compatible solution. The layer supports other popular standards, including ZigBee, and contributes to the overall power efficiency of the solution. 4. Summary As incandescent bulbs are being phased out around the world, more energy-efficient bulbs, such as CFLs and SSLs, have become the new standard for lighting. Driver ICs that improve power conversion and extend bulb lifetimes have already done a lot to save energy in these new bulbs. Now, by combining the driver technology with wireless IP connectivity, it is possible to create smart lighting networks that save even more. Bulbs can be turned on, turned off, and dimmed by using digital commands sent wirelessly from any computer, smartphone, or tablet. Lighting can also be controlled automatically by using network-based sensors that monitor room occupancy or light levels. NXP Semiconductors has developed the GreenChip chip set, which makes smart lighting a reality. The GreenChip platform enables multiple control options, including RF remote control, battery-powered switches, and control via IP-enabled sensors. The platform includes several features that minimize power consumption. It offers networking features that improve reliability, support easy extension, and enable quick integration with commercial and industrial building-management systems. All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 8 of 10
5. Legal information 5.1 Definitions Draft The document is a draft version only. The content is still under internal review and subject to formal approval, which may result in modifications or additions. NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. 5.2 Disclaimers Limited warranty and liability Information in this document is believed to be accurate and reliable. However, NXP Semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. In no event shall NXP Semiconductors be liable for any indirect, incidental, punitive, special or consequential damages (including - without limitation - lost profits, lost savings, business interruption, costs related to the removal or replacement of any products or rework charges) whether or not such damages are based on tort (including negligence), warranty, breach of contract or any other legal theory. Notwithstanding any damages that customer might incur for any reason whatsoever, NXP Semiconductors aggregate and cumulative liability towards customer for the products described herein shall be limited in accordance with the Terms and conditions of commercial sale of NXP Semiconductors. Right to make changes NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof. Suitability for use NXP Semiconductors products are not designed, authorized or warranted to be suitable for use in life support, life-critical or safety-critical systems or equipment, nor in applications where failure or malfunction of an NXP Semiconductors product can reasonably be expected to result in personal injury, death or severe property or environmental damage. NXP Semiconductors accepts no liability for inclusion and/or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customer s own risk. Applications Applications that are described herein for any of these products are for illustrative purposes only. NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Customers are responsible for the design and operation of their applications and products using NXP Semiconductors products, and NXP Semiconductors accepts no liability for any assistance with applications or customer product design. It is customer s sole responsibility to determine whether the NXP Semiconductors product is suitable and fit for the customer s applications and products planned, as well as for the planned application and use of customer s third party customer(s). Customers should provide appropriate design and operating safeguards to minimize the risks associated with their applications and products. NXP Semiconductors does not accept any liability related to any default, damage, costs or problem which is based on any weakness or default in the customer s applications or products, or the application or use by customer s third party customer(s). Customer is responsible for doing all necessary testing for the customer s applications and products using NXP Semiconductors products in order to avoid a default of the applications and the products or of the application or use by customer s third party customer(s). NXP does not accept any liability in this respect. Export control This document as well as the item(s) described herein may be subject to export control regulations. Export might require a prior authorization from competent authorities. 5.3 Trademarks Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. GreenChip is a trademark of NXP B.V. All information provided in this document is subject to legal disclaimers. NXP B.V. 2011. All rights reserved. Report Rev. 1 20 December 2011 9 of 10
6. Contents 1 Introduction............................ 3 2 An internet address for every bulb......... 3 3 The GreenChip approach................. 5 3.1 Very low standby power.................. 6 3.2 IP-based stack......................... 7 4 Summary.............................. 8 5 Legal information........................ 9 5.1 Definitions............................. 9 5.2 Disclaimers............................ 9 5.3 Trademarks............................ 9 6 Contents.............................. 10 Please be aware that important notices concerning this document and the product(s) described herein, have been included in section Legal information. NXP B.V. 2011. All rights reserved. For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com Date of release: 20 December 2011 Document identifier: