Hi, I've been tinkering and attempting to setup a laser-diode which hits a monolithic photodiode with op-amp, built in (opt101) and then use this small signal to open a +5v signal to an optoisolator which my pic reads.
i'm not sure if i'm setting something up wrong with the opt101 or with the transistors afterwards but its not working well.
at the moment, when i shine the laser on the opto, i see a potential difference of ~0.45v between the output pin and the positive+. i'm trying to either get this to open up the +5, directly or first use a common-emitter to amplify it to something that will make the second transistor happy. it's all going wrong, and my guess is that it may be related to the fact that the output potential is between that pin, and + as opposed to ground (which when measured with respect to output pin you see ~ 0.45+5v)
thanks in advance, any circuit diagrams would be much appreciated.
purpleidea@hotmail.com
_J
i'm not sure if i'm setting something up wrong with the opt101 or with the transistors afterwards but its not working well.
at the moment, when i shine the laser on the opto, i see a potential difference of ~0.45v between the output pin and the positive+. i'm trying to either get this to open up the +5, directly or first use a common-emitter to amplify it to something that will make the second transistor happy. it's all going wrong, and my guess is that it may be related to the fact that the output potential is between that pin, and + as opposed to ground (which when measured with respect to output pin you see ~ 0.45+5v)
thanks in advance, any circuit diagrams would be much appreciated.
purpleidea@hotmail.com
_J