resolution
PrintThe smallest amount of input signal change that an instrument or sensor can detect. The term, discrimination, is also used for resolution.
Resolution is determined by the instrument noise (either circuit or quantization noise) and the smallest change that is detectable by the display system of the instrument. For example, if you have a noiseless voltmeter that has 5 ½-displayed digits and is set to the 20V input range, the resolution of this voltmeter is 100 mVolt. This can be determined looking at the change associated with the least significant digit.
Now, if this same voltmeter had 10 counts of peak-to-peak noise, then the effective resolution is decreased to 1 mV, because any signal change less then 1 mV is indistinguishable from the noise.
For an A/D converter or digitizer with 12 bits resolution, this would correspond to one part if 4,096 or 0.024% of full scale. Frequency resolution is measured in Hz or in % of the actual frequency. Frequency counters often have their resolutions specified in the number of digits.
Units:
% or number of bits, or digits for a voltmeter
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