An OP AMP has CMRR = 100 dB and open-loop gain =250000.
Determine the common mode gain ACM
Answer:
ACM = 2.5
Explanation:
The common mode rejection ratio, is a parameter that is used to measure the ability of an Operational-Amplifier, to reject or eliminate the noises of same polarity. The common mode rejection ratio is given by the following formula:
CMMR = AV/ACM
for the value of CMMR in deciBels (dB), the formula becomes:
Answer:
ACM = 2.5
Explanation:
The common mode rejection ratio, is a parameter that is used to measure the ability of an Operational-Amplifier, to reject or eliminate the noises of same polarity. The common mode rejection ratio is given by the following formula:
CMMR = AV/ACM
for the value of CMMR in deciBels (dB), the formula becomes:
CMMR = 20 log(AV/ACM)
where,
CMMR = Common Mode Rejection Ratio = 100 dB
AV = Open Loop Gain = 250000
ACM = Common Mode Gain = ?
Therefore,
100 = 20 log (250000/ACM)
100/20 = log (250000/ACM)
10⁵ = 250000/ACM
ACM = 250000/10⁵
ACM = 2.5