I understand the diode anode/cathode identification but I have a BPW21R which is a phototransistor. It has two terminals as the base is driven by the light input. Datasheets tell me that there is a cathode connected to the package in a TO5 can but I can't see anything that tells me which is the cathode! My thinking is that the arrow points to the cathode therefore that is the emitter equivalent. Am I right?
Is this a common issue with phototransistors? Has someone worked it out already?
Thank you for your guidance.
Is this a common issue with phototransistors? Has someone worked it out already?
Thank you for your guidance.