I was asked to analyze this Op-amp circuit and I need a little bit of advice about it. I have presented my analysis about the circuit, kindly correct me wherever I am going wrong.
- If a positive voltage is applied at Vref then the negetive terminal should also necessarily have its voltage at the same.
- Hence a current will try to flow through the 100 ohm resistor into the ground, but will be unable to do so, since there is no circuit path. What I don't understand is what will happen in this case, will there be a current flowing through the amp feedback short path?
- If the reference voltage is negetive, a current may flow through the emitter, but what will be the voltage at the base? And even if a current flows through the emitter, will the reverse biased LED through the collector allow this.
Hence, I think the circuit is wrong, please give me your suggestions...
P.S. The diode D1 is a laser Diode, I don't know what that implies. Is it different from an LED diode?