Common-mode rejection ratio

<p>In <a href="/facts/Electronics/E4JhgISq">electronics</a>, the common mode rejection ratio (CMRR) of a <a href="/facts/Differential_amplifier/0MWj8eCR">differential amplifier</a> (or other device) is a metric used to quantify the ability of the device to reject <a href="/facts/Common-mode_signal/8GCxkDAb">common-mode signals</a>, i.e. those that appear simultaneously and <a href="/facts/Phase_(waves)/cpGtuVll">in-phase</a> on both inputs. An <a href="/facts/Idealization_(science_philosophy)/5LVmNhz0">ideal</a> differential amplifier would have infinite CMRR, however this is not achievable in practice. A high CMRR is required when a differential signal must be amplified in the presence of a possibly large common-mode input, such as strong <a href="/facts/Electromagnetic_interference/gv3DlKNr">electromagnetic interference</a> (EMI). An example is audio transmission over <a href="/facts/Balanced_line/XubfIRdc">balanced line</a> in <a href="/facts/Sound_reinforcement/s480anBh">sound reinforcement</a> or <a href="/facts/Sound_recording/BMbpAWkE">recording</a>.
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Common-mode rejection ratio open-in-new

Common-mode rejection ratio