I saw this specific mirror referred to in the related "Current Mirror Discussion" thread. I had a question about it, but I didn't want to thread jack.
This mirror has been referred to as the "V-mirror", or the "Gilbert Current Mirror".
--> If we are using an opamp to equalize the drain voltages between the two transistors, isn't there a potential for positive feedback (depending upon the load connected to the output side of the current mirror)? I believe that the path from the output of the opamp to its inverting terminal, and the path from its output to its negative terminal, *could* be the same path.
If I remember my nuts and bolts properly, I think that an opamp must have more negative feedback than positive feedback if it is to act stable (instead of a switch like a schmidt trigger). In this schematic, there is the potential for more positive feedback than negative feedback. Am I missing something?
This mirror has been referred to as the "V-mirror", or the "Gilbert Current Mirror".
--> If we are using an opamp to equalize the drain voltages between the two transistors, isn't there a potential for positive feedback (depending upon the load connected to the output side of the current mirror)? I believe that the path from the output of the opamp to its inverting terminal, and the path from its output to its negative terminal, *could* be the same path.
If I remember my nuts and bolts properly, I think that an opamp must have more negative feedback than positive feedback if it is to act stable (instead of a switch like a schmidt trigger). In this schematic, there is the potential for more positive feedback than negative feedback. Am I missing something?
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