PC817光耦-------最常用的光耦，用来实现两个不同电压间通讯。

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PC817 Series High Density Mounting Type Photocoupler PC817 Series P type are also available PC817IPC817P 5 000V rms h Lead forming type I type and taping reel type hh TUV VDE0884 approved type is also available as an option n Features 1 Current transfer ratio CTR MIN 50 at I F 5mA VCE5V 2 High isolation voltage between input and output Viso 3 Compact dualinline package PC817 1channel type PC827 2channel type PC837 3channel type PC847 4channel type 4 Recognized ......