On Tue, 27 Mar 2007 17:10:57 +0200, Fred Bartoli
r_AndThisToo wrote:
Jim Thompson a écrit :
On Tue, 27 Mar 2007 11:52:55 +0200, Fred Bartoli
r_AndThisToo wrote:
Jim Thompson a écrit :
See attachment.
WhatZit?
That is, what does it do?
VDD=2V
...Jim Thompson
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Sort of. Equation?
...Jim Thompson
From simple inspection:
ID(MP1) = I(R1) = ID(MP2)
MN1 and MN2 have identical constant bias current so:
*when IN2 IN1
V(MN1s)-V(MN2s)=V(IN1)-V(IN2)
then ID(MP3) = I(R3)-ID(MP2) = (V(IN2)-V(IN1))/R3 = ID(MP4)
then Vout = V(IN2)-V(IN1)
*when IN2 IN1
Vout obviously can't go negative because of the output circuit, but
also because ID(MP2) I(R3). Then the MN2/MP3 loop goes open and MP2
steals some bias current to MN2.
Good boy ;-)
...Jim Thompson
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