I need a quick interpretation on a particular phrase. I am putting together a lenghty document on common-mode rejection for op-amps, and I am stuck on the wording on Jiri Dostal's amplifier book.
Common-mode gain should be 0 in an ideal amplifier. With the inputs shorted to Vcm there should be no change in output voltage with any given change for Vcm.
The part I am getting stuck on is the wording. "Since the gain A and the rejection ratio X are usually of hte same order with well-designed operational amplifiers, the common-mode gain Acm is usually on the order of 1."
What does "order of 1" imply in Math Speak?
See attached for scans of this section.
Common-mode gain should be 0 in an ideal amplifier. With the inputs shorted to Vcm there should be no change in output voltage with any given change for Vcm.
The part I am getting stuck on is the wording. "Since the gain A and the rejection ratio X are usually of hte same order with well-designed operational amplifiers, the common-mode gain Acm is usually on the order of 1."
What does "order of 1" imply in Math Speak?
See attached for scans of this section.
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