# Op-Amp

4. A certain op-amp has an open-loop voltage gain of 100,000 and a common mode gain of 0.2. Determine the CMRR in dB.

5. Find the open loop gain and phase shift for an RC-lag circuit at the following frequencies: (i) 1 Hz (ii) 10 Hz (iii) 100 Hz (iv) 1000 Hz (v) 10000 Hz. Plot the curve of phase shift versus frequency curve in a Bode Plot. You may assume that fc = 100 Hz and Av = 100,000.

6. A certain amplifier has three internal amplifier stages with the following gains and critical frequencies:

Stage 1: Av1 = 40 dB, fc1 = 2 kHz

Stage 2: Av2 = 32 dB, fc2 = 40 kHz

Stage 3: Av3 = 20 dB, fc3 = 150 kHz

Determine the open-loop midrange gain in decibels and the total phase lag when f = fc1.

7. A certain amplifier has an open-loop midrange gain of 150,000 and an open-loop 3 dB bandwidth of 200 Hz. Given that the feedback factor is 0.002, what is the closed-loop bandwidth?

© BrainMass Inc. brainmass.com October 10, 2019, 2:28 am ad1c9bdddfhttps://brainmass.com/engineering/electrical-engineering/cmrr-rc-lag-circuit-bode-plot-open-loop-midrange-gain-378822

#### Solution Preview

Please see attached document for the solution to the given problems.

...

#### Solution Summary

This posting contains the solution to the given problems.