一种简单的室内照明能源获取方法

　　一种简单的室内照明能源获取方法

　　太阳能收集为连接传感器、控制节点、物联网设备和其他嵌入式应用提供了实用的解决方案。然而，它可以很难从太阳能电池中提取足够的能量，以适应这些应用的小形状因素。

　　不像大能量收集应用，这些设计通常会产生少量的能量收集电源。在开发系统能够在什么通常微瓦水平运行的设计师面临多重挑战。然而，通过使用电源管理IC（PMIC）Cypress半导体，工程师可以快速实现能量收集电源能够在超低功率运行。

　　Limited energy

　　By harvesting power from ambient energy sources， engineers can create designs that can run indefinitely with no additional power source. For the IoT， this approach is particularly attractive for small， wireless systems that have relied solely on battery power in the past. Using energy harvesting， developers can eliminate batteries entirely. For more power intensive designs， energy harvesting can substantially extend battery life， largely eliminating the need for periodic battery replacement.

　　In many designs， a typical solar energy harvesting system requires large solar cells or arrays to provide sufficient power. For tiny sensor systems， however， large solar cells are not suitable due to a desire for compact designs， or limited installation space at the target location.

　　The need for smaller solar cells further complicates energy harvesting for a typical indoor IoT design. Indoor light sources generate very small illumination levels， ranging from about 100 to 200 lux in a typical home， and from 250 to 500 lux in an office. Even well illuminated areas， such as drafting tables or workshops， offer light levels that are orders of magnitude below sunlight illumination levels.

　　Solar cell manufacturers have responded to the need for indoor solar cells with technologies such as amorphous silicon. Unlike crystalline silicon used in traditional solar cells， amorphous silicon possesses an irregular structure that absorbs more light than crystalline structures. Constructed from these specialized materials， solar cells such as those in the Panasonic Amorton family can generate power even at very low light levels （Figure 1）.