cfp - variant --> current coupled

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Yes true

depending on the supply voltage rails
so
the diode chain is required in the presence of a voltage step

for example (see picture)
if the polarization is made with a resistor
it is NOT important to protect the base
but if it is polarized by a constant current source
Yes

understand exactly what happens in this chain
think it is indeed no easy analysis

it is intuitively easy to understand
adding an apparently useless
as in the mirror of Wilson
with 3 or 4 Parts
 

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Drastic misunderstanding of how a Wilson current mirror functions.
http://en.wikipedia.org/wiki/Wilson_current_mirror

A non-linear voltage divider, driving a 2/1 voltage divider, driving a
BE junction and emitter resistor. And I can't even follow a purposely
curved or distorted logic to it after that. This certainly does not appear
to be a linear mirror of anything.

Put down the iron and step away from the fumes...
 
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Hi,

simmed the circuit from #15 with the only difference of replacing the output Transistors Q7/Q8 by the complementary 2SA1216/2SC2922 pair.
And compared it to the same circuit without the two diodes D2 and D3.
The only noteable and expectable difference was the roundabout 0.6V voltage drop over D2 and D3.
Amplitude response, THD level and spectrum and noise are virtually identical.
Rather the circuit without the diodes beeing ahead by a Yota.
Response to a rectangle signal is rather defined by the value of the compensation caps C1 and C2.
Removing the Caps C1 and C2 leads to damped ringing, but again both circuits behaving identical.
The absence of D2 and D3 doesn´t change anything.
So far none of he claims could be verified in simulation.
And so far no sensible technical explanation has been provided.
As long as not someone steps up with a sensible explanation, to me the "diode chain" looks like ´Money for nothing´.

jauu
Calvin
 
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