Samuel Groner
Well-known member
Hi
I'm currently trying to get some inside in discrete opamps; there's a great one from Dan Kennedy on FFs page (Great River Opamp2.pdf) which I tried to understand. Let's see:
* Q1: diff. input pair (I'm great, no? :green: )
* Q2-Q4: current mirror for Q1
* Q5: current source for Q1
* Q6: another current source
* Q9-Q11: another current mirror
Now I'm stuck with Q7 and Q8; at first they look like another diff. pair; but I would expect Q8 to be connected to Q9 for this. In "Designing Analog Chips" by Camenzind I found a similar topology (page 4-6, fig. 4-12) which would explain Q7. Q8 looks like a miller compensated voltage gain stage, but this is really a hopeless guess.
Any help?
Samuel
PS: you can download the mentioned book here.
I'm currently trying to get some inside in discrete opamps; there's a great one from Dan Kennedy on FFs page (Great River Opamp2.pdf) which I tried to understand. Let's see:
* Q1: diff. input pair (I'm great, no? :green: )
* Q2-Q4: current mirror for Q1
* Q5: current source for Q1
* Q6: another current source
* Q9-Q11: another current mirror
Now I'm stuck with Q7 and Q8; at first they look like another diff. pair; but I would expect Q8 to be connected to Q9 for this. In "Designing Analog Chips" by Camenzind I found a similar topology (page 4-6, fig. 4-12) which would explain Q7. Q8 looks like a miller compensated voltage gain stage, but this is really a hopeless guess.
Any help?
Samuel
PS: you can download the mentioned book here.