Phototransistor Amplifier Circuit. The phototransistor is generally in the form of a bipolar npn silicon transistor encapsulated in a cover with a transparent opening. 1 generates an output which transitions from a high state to a low state when light in the near infrared range is detected by the phototransistor.
Adjusting Sensitivity Of A Phototransistor Circuit Schmitt Trigger Circuit Electronics Projects from in.pinterest.com
However i am having trouble understanding the relationship between the phototransistor s collector current and the output of the amplifier i1d. The common collector and common emitter phototransistor circuits shown above will provide something closer to true digital switching behavior when a larger base resistor rb is used in the circuit. I m looking for an amplifier circuit to go with a phototransistor.
The output volt age vout is given as vout if r1 ip isc.
Design fundamentals for phototransistor circuits the common emitter amplifier circuit fig. It does not have a terminal connection to its base. The collector is taken to the supply voltage via a collector load resistor and the output is taken from the collector connection on the phototransistor. I appreciate the book suggestion but it does not appear to contain such examples.
