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CTR figure in Optos
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Grant Fair
Nov 29, 1995, 3:00:00 AM11/29/95
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I know that optoisolators (led-phototransistor types) have a
characteristic called CTR (current transfer ratio, I think). This is
usually given as a percentage - I have seen this range from 20% to 200%.
characteristic called CTR (current transfer ratio, I think). This is
usually given as a percentage - I have seen this range from 20% to 200%.
What does this mean? Is it related to any other opto characteristic,
such as speed, or current consumption?
Grant
P.Bennett
Nov 29, 1995, 3:00:00 AM11/29/95
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In article <60.7655.42...@canrem.com>, grant...@canrem.com (Grant Fair) writes...
It is the ratio of output current to input current. If the opto has a CTR of
50%, and you put 10 mA through the LED, you can expect the transistor to pass 5
mA.
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