Holding the input constant what is the worst case oamffset (drift)?
It does look like a novel idea.
Jam
It does look like a novel idea.
Jam
In this example, it is approximately 50mV (Q1 and Q3 held at the same temperature).
It depends on the matching of the current densities in Q1 and Q3. If the currents are scaled in the same proportion as the junction areas, a first order cancellation occurs, both statically and dynamically.
Yes, I have built it, tested it with real audio too: no obvious flaw.
I won't comment further in that direction since I have tin ears, but it sounds OK.
It is not a topology for the faint hearted though: the input impedance is negative, which can be disconcerting to the novice.
You know the base current of 2n3055 is wildly not a linear load.
Somehow need to add or subtract that drive current back into
the equation that will hold Q1's emitter drop constant.
Somehow need to add or subtract that drive current back into
the equation that will hold Q1's emitter drop constant.
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Or this way too, could hold those two emitters constant.
You might ask, why not a simple mirror across the top?
Yeah, but a mirror isn't so easy to bootstrap. Or is it???
M2 might want gate swing a few volts above the rail.
I keep trying to throw a gratuitous Taylor in there,
other weird solutions just keep popping in my head.
At least we are watching a collector and bouncing
that info as current to an active load on the emitter...
You might ask, why not a simple mirror across the top?
Yeah, but a mirror isn't so easy to bootstrap. Or is it???
M2 might want gate swing a few volts above the rail.
I keep trying to throw a gratuitous Taylor in there,
other weird solutions just keep popping in my head.
At least we are watching a collector and bouncing
that info as current to an active load on the emitter...
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