中國的一個(gè)新安全標(biāo)準(zhǔn)即將在今年十二月一日起生效，基本上，這很可能成為全球電源供應(yīng)器的實(shí)質(zhì)標(biāo)準(zhǔn)，因?yàn)槟壳敖^大多數(shù)的電源供應(yīng)器都在中國生產(chǎn)。 新的 GB 4943.1-2011 標(biāo)準(zhǔn)授權(quán)在電源供應(yīng)器上加注嚴(yán)格的沿面距離和電氣間隙規(guī)范警語。該規(guī)范要求設(shè)計(jì)人員針對海拔 2000 公尺以上的設(shè)備中所使用的電源供應(yīng)器，將其一次側(cè)與二次側(cè)間隔距離增加為1.48倍，否則要在產(chǎn)品上新增警告標(biāo)示。 不過，電子廠商都不喜歡加注警告卷標(biāo)。因?yàn)閷κ紫?，許多住在高海拔地區(qū)的使用者就不太可能購買這類產(chǎn)品；此外，在產(chǎn)品上加注的警語會(huì)占用寶貴的空間──制造商通常喜歡將這些空間用來行銷自己的產(chǎn)品。最后，任何警告標(biāo)志都很可能在一定程度上降低消費(fèi)者對產(chǎn)品安全的信心。 “沒有人愿意在他們的產(chǎn)品包裝貼上“不適用海拔2000公尺以上環(huán)境”的卷標(biāo)，”Power Integrations公司行銷副總裁 Doug Bailey說。該公司稍早前才推出全新的高能效離線式開關(guān)IC，可協(xié)助設(shè)計(jì)師開發(fā)出符合中國新版標(biāo)準(zhǔn)的手機(jī)和其它產(chǎn)品。 高海拔地區(qū)的空氣稀薄，通常也不太潮濕，因此，在用來保護(hù)設(shè)備免受電壓突波傷害的標(biāo)準(zhǔn)放電管(spark gap)中，會(huì)有較高的機(jī)率出現(xiàn)火花。然而在中國，一些人口稠密的地區(qū)就集中在海拔2000公尺以上。 “中國人設(shè)定了比實(shí)際應(yīng)用更加嚴(yán)苛的標(biāo)準(zhǔn)，”Bailey說。他表示，在西方國家，也已經(jīng)有人感受到新標(biāo)準(zhǔn)將帶來的沖擊。由于幾乎所有的電源都在中國生產(chǎn)，因此這些產(chǎn)品都會(huì)符合新標(biāo)準(zhǔn)，或是加注警告標(biāo)志。 Bailey表示，為符合中國標(biāo)準(zhǔn)，設(shè)計(jì)人員可以透過添加較大的間隙來重新設(shè)計(jì)自己的電源，但這么做卻需要使用更昂貴的光耦合器?！叭绻愦蛩阒匦略O(shè)計(jì)，最簡單的方法，就是去買一顆更大的光耦合器，”Bailey說?！安贿^，更好的辦法是用我們的新芯片。”

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Power Integrations 的 LinkSwitch-HP IC并不是使用光耦合器和相關(guān)的反饋電路，它使用控制算法和專有的主電源變壓器和輸出二極管，來確定從一次側(cè)到隔離的二次側(cè)的電源總量。據(jù)Bailey表示，這種做法可減少組件數(shù)量、節(jié)省空間和成本，同時(shí)也提高了可靠性。 Power Integrations的一次側(cè)調(diào)節(jié)(PSR)已經(jīng)廣泛用在大功率應(yīng)用中。該公司表示，LinkSwitch-HP組件也具備多?？刂萍軜?gòu)，能進(jìn)一步提升PSR的性能，使其適用于從9W到90W的電源供應(yīng)器應(yīng)用。 LinkSwitch-HP 可根據(jù)當(dāng)下的線性和負(fù)載條件自動(dòng)選擇控制模式，以最佳化轉(zhuǎn)換效率及響應(yīng)瞬態(tài)負(fù)載要求，同時(shí)最大限度地降低輸出紋波和音訊噪聲。連續(xù)導(dǎo)通模式 (CCM) 操作會(huì)降低有效值電流，可在處于 132 kHz 滿載操作頻率時(shí)，產(chǎn)生較高的效率及更少的散熱，因此可使用更小的磁性組件和 LC 后置濾波器組件。 LinkSwitch-HP IC 可在 230 VAC 條件下無負(fù)載功耗低于 30 mW；0.1 W 輸入功率的效率超過 50%；輕易符合全球所有的外部電源供應(yīng)器節(jié)能法規(guī)，例如 ErP (EuP)、能源之星 EPS V2.0 及歐盟委員會(huì)節(jié)能化設(shè)計(jì)指令第 2 階段。 本文授權(quán)編譯自EE Times，版權(quán)所有，謝絕轉(zhuǎn)載 編譯： Joy Teng 本文下一頁：參考英文原文：Chinese safety spec may be de facto global standard，by Dylan McGrath

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{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.