硅實(shí)驗(yàn)室能量收集參考設(shè)計(jì)的實(shí)踐回顧

　　低功耗無(wú)線傳感器在工業(yè)和醫(yī)療應(yīng)用中越來(lái)越普遍，遠(yuǎn)程測(cè)量橋梁和建筑物的壓力，甚至人類的心臟壓力。傳感器節(jié)點(diǎn)需要超低功耗，因?yàn)楦鼡Q電池可能代價(jià)高昂，不切實(shí)際，甚至不可能。在這些應(yīng)用中，環(huán)境能源的獲取成為一個(gè)高度優(yōu)先事項(xiàng)，甚至是必要的。如果你考慮這樣的設(shè)計(jì)，硅實(shí)驗(yàn)室制造一個(gè)便宜的能量收集板，它既是概念的證明，也是設(shè)計(jì)你自己應(yīng)用程序的跳板。

　　硅實(shí)驗(yàn)室的能量收集參考設(shè)計(jì)（見(jiàn)圖1）由一個(gè)無(wú)線傳感器節(jié)點(diǎn)和一個(gè)USB無(wú)線適配器組成。無(wú)線傳感器節(jié)點(diǎn)是由太陽(yáng)能電池供電，雖然有一個(gè)輔助輸入，將允許電源來(lái)自其他能源采集的替代品，如熱，壓電或射頻。傳感器節(jié)點(diǎn)采用了Silicon Labs si1012a無(wú)線單片機(jī)測(cè)量溫度，光照水平和收費(fèi)水平，無(wú)線傳輸數(shù)據(jù)到EZRadioPRO?USB適配器，從而使用一個(gè)單獨(dú)的Silicon Labs C8051F342單片機(jī)和4431無(wú)線電。這次審查將使董事會(huì)通過(guò)它的步伐，建議在無(wú)線傳感器節(jié)點(diǎn)的能量收集源有意義。

　　The sensor node is powered entirely by a solar cell， with energy stored in an Infinite Power Solutions’ THINERGY? thin-film battery with power management handled by Linear Technology’s LTC4071 regulator chip （see Figure 2）。 The system is designed for ultra-low power operation， with the Si1012 consuming only 50 nA when it is not transmitting data. The leakage current of the energy harvesting supply is approximately 3 μA， which can be overcome by as little as 50 lux shining on the solar cell. When the battery is fully charged， the system can operate for approximately seven days in total darkness or indefinitely when exposed to light. The system can operate using either indoor lighting （200 lux） or sunlight （10，000 lux）。 Silicon Labs puts the life expectancy of the sensor board at 15 years， over which time it can deliver 7000 mA-H.