& d, ~7 t) {6 ]5 X3 h( M$ _6 sOutput voltage (VOUT) is the product of photocurrent (IOUT) and loading resistor (RSS).: C [# k) t. r& U, ]
A right loading resistor should be chosen to meet the requirement of maximum ambient light and the output saturation voltage: VOUT(max)=IOUT(max) × RSS < Vsat= VDD-1.5V. ( w* U! _( i+ m* O& X To avoid 60Hz ripple from fluorescent lamps, we suggest that the time constant must be greater than 0.5 second. RSS × CL > 0.5s (empirical data). . o2 u/ P" G7 d! h& P $ M% v: y! ]; H8 L1 s5 J然后右侧是采样输出3 m" z, m# T* V/ a2 E+ f. ]
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RSS和光电流乘积是输出电压5 X7 I- P2 \, r
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调节外界光强,会输出不同的采样值,然后在一个光强范围内,采样值会变化,但是超出范围,就饱和了。我的目的是调节RSS,使得光强范围扩大到0-10LX。: t* `( @& I* V+ |! |* X' R; |8 p1 s' y
然后我现在测试了,RSS在1M的时候 ,3.5LX饱和, 3 A) o, s. k& A- p/ R然后,将Rss减小到500K的时候,0.2LX饱和 # { ?. \/ y0 ^1 P: B; e所以现在很纳闷,,难道不是应该减小RSS的值来增大光强范围吗,为什么减小了RSS,反而光强可调范围反而减小了+ q9 I# H- h y1 t% S