- #1
etf
- 179
- 2
Hi!
Here is my task:
Current sources Iss which are used for differential amplifier in photo c) are shown in photos a) and b). DC voltages VB1 and VB2 provide saturation for all MOSFETS. Calculate ratio of CMRR of differential amplifier with current source from image a) and CMRR of differential amplifier from image b). gm1, gm2, rds1 and rds2 are known.
So here I have to analyse two differential amplifiers:
1. I have to find CMRR1 for differential amplifier c) with current source a)
2. I have to find CMRR2 for differential amplifier c) with current source b)
Final result would be CMRR1/CMRR2. My question is, is there better approach in solving this problem? There would be a lot of work in previous steps. Is it possible, for example, to analyse differential amplifier c) with current source b) , calculate CMRR2 and use CMRR2 to calculate CMRR1 (putting gm2=0, rds2=∞ in CMRR2) ?
Here is my task:
Current sources Iss which are used for differential amplifier in photo c) are shown in photos a) and b). DC voltages VB1 and VB2 provide saturation for all MOSFETS. Calculate ratio of CMRR of differential amplifier with current source from image a) and CMRR of differential amplifier from image b). gm1, gm2, rds1 and rds2 are known.
So here I have to analyse two differential amplifiers:
1. I have to find CMRR1 for differential amplifier c) with current source a)
2. I have to find CMRR2 for differential amplifier c) with current source b)
Final result would be CMRR1/CMRR2. My question is, is there better approach in solving this problem? There would be a lot of work in previous steps. Is it possible, for example, to analyse differential amplifier c) with current source b) , calculate CMRR2 and use CMRR2 to calculate CMRR1 (putting gm2=0, rds2=∞ in CMRR2) ?