中国新安规或成全球电源供应器标准

中国的一个新安全标准即将在今年十二月一日起生效，基本上，这很可能成为全球电源供应器的实质标准，因为目前绝大多数的电源供应器都在中国生产。 新的 GB 4943.1-2011 标准授权在电源供应器上加注严格的沿面距离和电气间隙规范警语。该规范要求设计人员针对海拔 2000 公尺以上的设备中所使用的电源供应器，将其一次侧与二次侧间隔距离增加为1.48倍，否则要在产品上新增警告标示。 不过，电子厂商都不喜欢加注警告卷标。因为对首先，许多住在高海拔地区的使用者就不太可能购买这类产品；此外，在产品上加注的警语会占用宝贵的空间──制造商通常喜欢将这些空间用来行销自己的产品。最后，任何警告标志都很可能在一定程度上降低消费者对产品安全的信心。 “没有人愿意在他们的产品包装贴上“不适用海拔2000公尺以上环境”的卷标，”Power Integrations公司行销副总裁 Doug Bailey说。该公司稍早前才推出全新的高能效离线式开关IC，可协助设计师开发出符合中国新版标准的手机和其它产品。 高海拔地区的空气稀薄，通常也不太潮湿，因此，在用来保护设备免受电压突波伤害的标准放电管(spark gap)中，会有较高的机率出现火花。然而在中国，一些人口稠密的地区就集中在海拔2000公尺以上。 “中国人设定了比实际应用更加严苛的标准，”Bailey说。他表示，在西方国家，也已经有人感受到新标准将带来的冲击。由于几乎所有的电源都在中国生产，因此这些产品都会符合新标准，或是加注警告标志。 Bailey表示，为符合中国标准，设计人员可以透过添加较大的间隙来重新设计自己的电源，但这么做却需要使用更昂贵的光耦合器。“如果你打算重新设计，最简单的方法，就是去买一颗更大的光耦合器，”Bailey说。“不过，更好的办法是用我们的新芯片。”

y6nesmc

Power Integrations 的 LinkSwitch-HP IC并不是使用光耦合器和相关的反馈电路，它使用控制算法和专有的主电源变压器和输出二极管，来确定从一次侧到隔离的二次侧的电源总量。据Bailey表示，这种做法可减少组件数量、节省空间和成本，同时也提高了可靠性。 Power Integrations的一次侧调节(PSR)已经广泛用在大功率应用中。该公司表示，LinkSwitch-HP组件也具备多模控制架构，能进一步提升PSR的性能，使其适用于从9W到90W的电源供应器应用。 LinkSwitch-HP 可根据当下的线性和负载条件自动选择控制模式，以最佳化转换效率及响应瞬态负载要求，同时最大限度地降低输出纹波和音讯噪声。连续导通模式 (CCM) 操作会降低有效值电流，可在处于 132 kHz 满载操作频率时，产生较高的效率及更少的散热，因此可使用更小的磁性组件和 LC 后置滤波器组件。 LinkSwitch-HP IC 可在 230 VAC 条件下无负载功耗低于 30 mW；0.1 W 输入功率的效率超过 50%；轻易符合全球所有的外部电源供应器节能法规，例如 ErP (EuP)、能源之星 EPS V2.0 及欧盟委员会节能化设计指令第 2 阶段。 本文授权编译自EE Times，版权所有，谢绝转载 编译： Joy Teng 本文下一页：参考英文原文：Chinese safety spec may be de facto global standard，by Dylan McGrath

相关阅读：
• 固纬推出可编程直流/交流电源供应器APS-1102
• 明纬推出SDR-240高效薄型轨道式电源供应器
y6nesmc

{pagination} Chinese safety spec may be de facto global standard Dylan McGrath SAN FRANCISCO—A new Chinese safety standard set to go into effect Dec. 1 could essentially become a de facto global standard for power supplies, since the vast majority of all power supplies are now manufactured there. The standard, GB 4943.1-2011, mandates the use of warning labels on power supplies that do not meet strict creepage and clearance rules. Similar to another standard created by product safety certification organization Underwriters Laboratories Inc., UL 60950-2007, the Chinese standard requires designers to increase the primary-to-secondary clearance by a factor of 1.48 for power supplies used in equipment at altitudes exceeding 2,000 meters (6,562 feet) or add a warning label stating that it should not be used above that altitude. Electronics vendors are loathe to add warning labels to products for a number of reasons. For starters, anyone who lives or travels to high altitudes would be less likely to buy a product that is not intended for use above 6,562 feet. Also, placing a warning label on the product would take up valuable space that companies typically prefer to use for their own marketing. And any warning label is likely to decrease consumer confidence in the safety of the product at some level. "Nobody wants to put a sticker on their box that says, 'Don't use above 2,000 meters,' " said Doug Bailey, vice president of marketing at Power Integrations Inc. Power Integrations introduced Tuesday (July 24) a new family of energy-efficient, off-line switcher ICs that can help designers of lower-power charges for mobile phones and other products comply with the new Chinese standard. At high altitudes, where the air is thinner and typically less humid, there is a higher danger of sparking across the standard spark gap used to protect against voltage surges. China contains several populated regions at altitudes over 2,000 meters. "The Chinese have put in place what is for all practical purposes a stricter standard than the rest of the world," Bailey said. According to Bailey, few people in the West appear to be aware of the new standard or its ramifications. Since virtually all power supplies are built in China, they will have to comply with the standard or apply the warning sticker, he said. Bailey said designers can redesign their power supplies to meet the Chinese standard by adding a larger gap, but that would also require adding a more powerful and more expensive opto-coupler. "If you are going to do a redesign, the simple thing is to buy a bigger opto," Bailey said. "But a better way, in our opinion, is to buy our chip." Power Integrations' LinkSwitch-HP ICs use control algorithms and the properties of the main power transformer and output diode—rather than optocouplers and related feedback circuitry—to determine the amount of power to deliver from the primary to the isolated secondary side. According to Bailey, this method reduces component count, saving space and cost while also enhancing reliability. Power Integrations' primary-side regulation (PSR) was popularized more than a decade ago for higher power applications. According to the company, the LinkSwitch-HP devices also feature a multi-mode control architecture that radically advances the state of the art for PSR, making it a viable approach for power-supply applications from 9 W to 90 W. LinkSwitch-HP devices automatically select their control mode according to prevailing line and load conditions to optimize conversion efficiency and response to transient load demands, while minimizing output ripple and audible noise, according to the company. Continuous-conduction-mode (CCM) operation results in reduced RMS currents, leading to higher efficiency and less heat dissipation, while 132 kHz, full-load operating frequency enables the use of smaller magnetics and LC post-filter components, the company said. LinkSwitch-HP ICs are also capable of no-load power consumption of less than 30 mW at 230 VAC and are more than 50 percent efficient at 0.1 W input power, meeting all global energy efficiency regulations for external power supplies, according to the company. Sampling now, the LinkSwitch-HP devices are offered in two different package options: eSIP-7C and eDIP-12B, starting at 42 cents each in 10,000-piece quantities (LNK6763V), according to Power Integrations. Two supporting evaluation demo boards are available upon request, the company said.