To make a good car you need good parts, to make a good amplifier too. One of them are the CCS, LTspice provides ideal CCS, but they are not real
in practice, in certain positions within the design of an amplifier
it is important that a CCS has the minimum influence,
especially when it is subjected to large voltage variations. For this I show you the best CCS that I have been able to design
and that I use in some stages.
Of course the choice of components also plays an important factor.
in practice, in certain positions within the design of an amplifier
it is important that a CCS has the minimum influence,
especially when it is subjected to large voltage variations. For this I show you the best CCS that I have been able to design
and that I use in some stages.
Of course the choice of components also plays an important factor.
Attachments
This current source output is roughly proportional to absolute temperature. Variation vs V2 depends on the relative currents in Q1 and Q3. Variation vs V3 could be quite strong, so long as the resistor values are properly chosen.
I agree with Minek. Can you show it with actual values?
I agree with Minek. Can you show it with actual values?
How about this one:
Actually this CCS is made up by two CCS that feed their output through each others reference, making it very stable over a wide voltage range.Extremely high PSRR, good step response. Only downside is that unlike the ideal CCS, this one needs a pretty high minimum voltage to operate.
Current is set by the two outermost resistors. The two innermost resistors may not be needed, but could help with stability of the cascodes a bit. All resistors need to have the same value.
Actually this CCS is made up by two CCS that feed their output through each others reference, making it very stable over a wide voltage range.Extremely high PSRR, good step response. Only downside is that unlike the ideal CCS, this one needs a pretty high minimum voltage to operate.
Current is set by the two outermost resistors. The two innermost resistors may not be needed, but could help with stability of the cascodes a bit. All resistors need to have the same value.
