The circuit below is part of a circuit I am analyzing.
The non inverting terminal has 2.5VDC always.
Note that +5VA is 5 Volts Analog - not AC.
I am confirming that my thoughts are correct.
The circuit operates as follows:
1) Left node of R37 has a voltage less than 2.5V --> op amp output is D21 voltage drop above 2.5 V --> PTRAN is OFF. Circuit is isolated from Q5 collector.
2) Left node of R37 is above 2.5V. Here the op amp will try to reduce the non inverting terminal but cant because of D21.
This causes the output to drop to about -5V causing the PTRAN to turn on - shorting the output of the non inverting terminal to the collector of Q5.
Any issues with my logic? Thanks for the support.
The non inverting terminal has 2.5VDC always.
Note that +5VA is 5 Volts Analog - not AC.
I am confirming that my thoughts are correct.
The circuit operates as follows:
1) Left node of R37 has a voltage less than 2.5V --> op amp output is D21 voltage drop above 2.5 V --> PTRAN is OFF. Circuit is isolated from Q5 collector.
2) Left node of R37 is above 2.5V. Here the op amp will try to reduce the non inverting terminal but cant because of D21.
This causes the output to drop to about -5V causing the PTRAN to turn on - shorting the output of the non inverting terminal to the collector of Q5.
Any issues with my logic? Thanks for the support.