Statistics show that 10 billion external power adapters were in use in 2001, reaching 15 billion by 2006. Based on a 6:4 ratio of switching power supplies to mains frequency power supplies, 6 billion mains frequency power adapters were in use, and this number was increasing at a rate of approximately 12% annually. China is the world's largest producer of mains frequency power adapters. In 2001, China's total power adapter production was approximately 400 million units, with sales reaching US$732 million. It is estimated that in 2006, China's daily production of mains frequency power adapters alone was approximately 1.6 million units (based on a 10-month production period and 25 days per month), accounting for 65% of global production. In general, the main challenges faced by Chinese home appliance exporters include at least the following aspects: 1. Increasingly strong international awareness of environmental protection and energy conservation; 2. The power frequency transformer industry is a traditional labor-intensive industry with almost no room for technological development; 3. The United States, the European Union, and other countries around the world have increasingly stringent requirements for standby power consumption and are enacting legislation to enforce them; 4. New solutions must be found for standby power saving; 5. The dual pressure of cost and performance requires chip designers to provide comprehensive and effective technical support. How to address these challenges is a serious issue that all external power adapter and home appliance component purchasers need to consider. Below, we will specifically discuss how the JAYTREE standby power saving chip NA22150P solves the standby power consumption problem and meets the above challenges. NA22150P Standby Power Saving Chip Function Overview The NA22150P standby power saving chip is a newly launched chip from Shenzhen Guanghuayuan Technology Co., Ltd., designed for external power adapters to achieve ultra-low standby power consumption (≤0.1W) (as shown in Figure 1). [img=320,143]http://cms.cn50hz.com/files/RemoteFiles/20090204/261781001.jpg[/img] Figure 1: Simplified block diagram of ultra-low standby power consumption technology. The operating power supply is formed by providing the operating voltage to the control circuit using a constant current source (e.g., composed of active components like a mirrored transistor), with a Zener diode added at the cold junction. A typical application is the use of this method in ON Semiconductor chips in switching power supply circuits. VCC is formed in a direct high-voltage form (NCP1012, etc.). The mirrored constant current source circuit is shown in Figure 2. [img=213,295]http://cms.cn50hz.com/files/RemoteFiles/20090204/261781002.jpg[/img] Figure 2: Mirrored constant current source circuit. Self-synchronizing switches, as we know, require synchronization to achieve zero-crossing triggering, ensuring that the zero-crossing point of the applied voltage matches the trigger signal of the BCR (currently the primary power switch), thus avoiding impact on the device itself, the load, and the power supply when in a non-zero state. This is a well-understood concept. Here, we propose the concept of synchronization on the first cycle: Generally, self-synchronizing devices (such as the optocoupler-controlled thyristor MOC3020), upon microscopic analysis, are not synchronized on the first cycle, while ours achieves synchronization on the first cycle, improving reliability. Simply put, regardless of when the trigger signal (which can be DC) is applied, the BCR only turns on at the zero-crossing point (Figure 3). [img=350,141]http://cms.cn50hz.com/files/RemoteFiles/20090204/261781003.jpg[/img] Figure 3: MOC3020 structural circuit diagram. Micro-current detection is a key technology, employing a Hall effect device placed within an open ring. The principle is self-evident, as shown in Figure 4. [img=245,177]http://cms.cn50hz.com/files/RemoteFiles/20090204/261781004.jpg[/img] Figure 4: Schematic diagram of micro-current detection. Weak signal conditioning circuit: This circuit is another key aspect of this technology. We directly use a high-sensitivity comparator, primarily based on cost and space considerations. High-voltage isolation transmission has two forms: magnetic and optical-to-electrical. Considering the need for 4000V high-voltage isolation, we adopted an optical-to-electrical mode combined with our self-synchronization circuit, a perfect match (Figure 5). [img=363,158]http://cms.cn50hz.com/files/RemoteFiles/20090204/261781005.jpg[/img] Figure 5: Usage and wiring diagram of one product structure. Its installation process is very simple. Without changing the original industrial frequency power adapter's manufacturing process, for example, using an industrial frequency power adapter made of ordinary silicon steel sheet material (e.g., H50 model), simply connect the application-specific integrated circuit (ASIC) in series into the circuit. As shown in Figure 6. [img=340,164]http://cms.cn50hz.com/files/RemoteFiles/20090204/261781006.jpg[/img] Figure 6: Wiring structure diagram (can be used for both AC/AC and AC/DC). Comprehensive Solution and Main Applications The comprehensive standard of Energy Star consists of two basic points: "no-load energy consumption" and "load energy efficiency". The low-power standby issue has already been addressed. The following methods address load energy efficiency: using high-permeability silicon steel sheets; reducing the current density of copper wires; selecting the optimal number of turns per volt; for AC/DC, replacing ordinary silicon diodes with large voltage drops with Schottky diodes; and in terms of manufacturing processes, choosing larger PCB copper-plated areas and thicker conductor cross-sections. In terms of application areas, the primary focus is on industrial frequency power adapters. Secondly, there's energy saving in mechanical electricity meters. Mechanical electricity meters mainly consist of a voltage element and a current element. This technology allows the voltage element (voltage coil) to be disconnected from the power supply when the meter is not measuring, thus achieving energy saving. It automatically reconnects when current flows through the current element (current coil). Thirdly, there are energy-saving sockets. Currently, there are no precedents for similar technologies. Similar technology, applied to sockets to achieve standby energy saving, produces products that resemble power converters, plugging between the power socket and the appliance plug. These automatically detect standby signals from appliances and cut off power, while also accepting remote control power-on signals to connect power. When appliances controlled by infrared remotes are turned off, they don't need to be unplugged. The most advanced technology can control power consumption as low as 0.5W. However, this technology is relatively expensive and has limited applicability, making widespread adoption difficult. This technology would also boost China's exports, as standby power consumption has become a "green barrier" for appliance exports. Having such technology to support this would act as a "green lever." However, from the manufacturers' perspective, most only consider pre-sales issues, neglecting the energy consumption aspect of product use. Connecting to a mains frequency adapter inevitably increases costs. Therefore, our current focus is primarily on providing this technology support to high-performance appliances, especially those exported to developed countries like Europe and America. Experiments have shown that the energy efficiency requirements of Energy Star are met across the power range of 3-150W, and we have comprehensive solutions and technical support. The test result from the Quality Testing Center of the Fifth Research Institute of Electronics, Ministry of Information Industry—China Saibao (Headquarters) Laboratory—is 0.09W. A slight drawback is that it currently only supports high-voltage AC input and cannot be used with DC input; low-voltage, high-current operation is also not ideal at present. However, we will further develop and design a more perfect solution. (He Shuguang, Shenzhen Guanghuayuan Technology Co., Ltd.)