Hi All,
Just got a quick question regarding the attached circuit.
(Source:http://picmania.garcia-cuervo.net/r..._high-level_loads_with_optocouplers_83704.pdf)
It says;
"
"
I don't understand how. If Q1 is conducting, would the voltage between the collector and emitter of the optocoupler not be whatever the source voltage is? I bet it is just my lack of understanding of something, but I just can't get my head around it.
Thanks
Just got a quick question regarding the attached circuit.
(Source:http://picmania.garcia-cuervo.net/r..._high-level_loads_with_optocouplers_83704.pdf)
It says;
"
The voltage
rating of the phototransistor is irrelevant since its
maximum collector-emitter voltage is the base emitter
voltage of Q1 (about 0.7 V).rating of the phototransistor is irrelevant since its
maximum collector-emitter voltage is the base emitter
"
I don't understand how. If Q1 is conducting, would the voltage between the collector and emitter of the optocoupler not be whatever the source voltage is? I bet it is just my lack of understanding of something, but I just can't get my head around it.
Thanks
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