Question

Find the differential mode gain of differential amplifier with CMRR of 5200 and common mode gain of 0.015V/V

• A. 0.012V/V
• B. 120V/V
• C. 7.8V/V
• D. 78V/V

Hint:

CMRR is a measure of the amplifier's ability to reject common-mode signals, and is a key indicator of amplifier performance.

Answer 1

The Correct Option is D

Step 1: The Common Mode Rejection Ratio (CMRR) is defined as the ratio of differential gain to the common mode gain. \[ CMRR = \frac{A_d}{A_{cm}} \] where \( A_d \) is the differential mode gain and \( A_{cm} \) is the common mode gain.
Step 2: We are given the CMRR = 5200 and \( A_{cm} = 0.015V/V \). We need to find \( A_d \). \[ A_d = CMRR \times A_{cm} = 5200 \times 0.015 = 78 \] Therefore the differential mode gain is 78 V/V.