C
Christian Rausch
- Jan 1, 1970
- 0
Hello everybody,
Q1.
Shot noise, as stated in Horowitz&Hill, ch7.11, p.432, shows a noise current
of
Inoise(rms) = sqrt(2*q*Idc*B)
with q:electron charge, B:bandwidth and Idc:the DC current,
but this formula "assumes that the charge carriers making up the current act
independently. This is indeed the case for charges crossing a barrier, as
for example the current in a junction diode...but is not true for the
important case of metallic conductors, where there are long-range
correlations between charge carriers..."
Does anybody know what the exact criterion for this 'independence of the
charge carriers' is?
Are there situations with 'partial' shot noise?
Q2.
At the bottom of the first column of p.432, H&H mention that the standard
transistor current source runs quieter than shot-noise-limited. Anybody out
there who knows a little more (literature, math) about this?
Anybody who can give me a reference on how to calculate the output noise
current of a transistor current source?
Thanks for any advice!
Christian
Q1.
Shot noise, as stated in Horowitz&Hill, ch7.11, p.432, shows a noise current
of
Inoise(rms) = sqrt(2*q*Idc*B)
with q:electron charge, B:bandwidth and Idc:the DC current,
but this formula "assumes that the charge carriers making up the current act
independently. This is indeed the case for charges crossing a barrier, as
for example the current in a junction diode...but is not true for the
important case of metallic conductors, where there are long-range
correlations between charge carriers..."
Does anybody know what the exact criterion for this 'independence of the
charge carriers' is?
Are there situations with 'partial' shot noise?
Q2.
At the bottom of the first column of p.432, H&H mention that the standard
transistor current source runs quieter than shot-noise-limited. Anybody out
there who knows a little more (literature, math) about this?
Anybody who can give me a reference on how to calculate the output noise
current of a transistor current source?
Thanks for any advice!
Christian