Enter the differential gain and the common mode gain into the Calculator. The calculator will evaluate the CMRR (common mode rejection ratio).
CMRR (common mode rejection ratio) Formula
CMRR = Adiff/Acom
Variables:
- CMRR is the CMRR (common mode rejection ratio) ()
- Adiff is the differential gain
- Acom is the common mode gain
To calculate CMRR (common mode rejection ratio), divide the differential gain by the common mode gain.
How to Calculate CMRR (common mode rejection ratio)?
The following steps outline how to calculate the CMRR (common mode rejection ratio).
- First, determine the differential gain.
- Next, determine the common mode gain.
- Next, gather the formula from above = CMRR = Adiff/Acom.
- Finally, calculate the CMRR (common mode rejection ratio).
- After inserting the variables and calculating the result, check your answer with the calculator above.
Example Problem :
Use the following variables as an example problem to test your knowledge.
differential gain = 7.2
common mode gain = 8.9
Frequently Asked Questions
What is differential gain?
Differential gain refers to the amplification factor by which a device amplifies the difference between two input signals.
Why is the common mode rejection ratio (CMRR) important?
CMRR is crucial because it measures a device’s ability to reject common mode signals, such as noise, that are present on both input lines, ensuring the fidelity of the differential signal.
How can CMRR affect the performance of an amplifier?
A higher CMRR indicates better performance in rejecting noise and interference, leading to clearer and more accurate amplification of the intended signal.
Can CMRR be improved in an existing circuit?
Yes, CMRR can be improved by balancing the impedances in the input circuit, using better matched components, or employing feedback mechanisms to reduce common mode gain.
