Short-circuit
New Member
Hi
I have a device that should be triggered by light. So, I took a simple phototransistor and transistor, soldered their collectors (and connected them to 12V source), emitter of phototrans. to the base of trans. and emitter of trans. out to the device. It kinda works, but not the way I'd like. :roll: The device needs 12V to operate, but the max. voltage 'behind' transistor (on its emitter) is cca 5.9V (with max. illumination of the phototrans.) Problem No.2: the transistor gets seriously hot after 5-15sec of operation. :shock:
Question: which transistor should I use? Phototrans. is OK. Trans. is of NPN type...
Oh yes, I tryed using a photodiode, but the voltage on emitter was even smaller (1.2-1.9V). :?:
Tenx
I have a device that should be triggered by light. So, I took a simple phototransistor and transistor, soldered their collectors (and connected them to 12V source), emitter of phototrans. to the base of trans. and emitter of trans. out to the device. It kinda works, but not the way I'd like. :roll: The device needs 12V to operate, but the max. voltage 'behind' transistor (on its emitter) is cca 5.9V (with max. illumination of the phototrans.) Problem No.2: the transistor gets seriously hot after 5-15sec of operation. :shock:
Question: which transistor should I use? Phototrans. is OK. Trans. is of NPN type...
Oh yes, I tryed using a photodiode, but the voltage on emitter was even smaller (1.2-1.9V). :?:
Tenx