ADAV4622
Rev. B | Page 18 of
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TERMINOLOGY
Dynamic Range
The ratio of a full-scale input signal to the integrated input
noise in the pass band (20 Hz to 20 kHz), expressed in decibels
(dB). Dynamic range is measured with a −60 dB input signal
and is equal to (S/[THD+N]) + 60 dB. Note that spurious
harmonics are below the noise with a −60 dB input, so the noise
level establishes the dynamic range. The dynamic range is
specified with and without an A-weight filter applied.
Pass Band
The region of the frequency spectrum unaffected by the
attenuation of the digital decimator’s filter.
Pass-Band Ripple
The peak-to-peak variation in amplitude response from equal
amplitude input signal frequencies within the pass band,
expressed in decibels.
Stop Band
The region of the frequency spectrum attenuated by the digital
decimator’s filter to the degree specified by stop-band
attenuation.
Gain Error
With a near full-scale input, the ratio of the actual output to the
expected output, expressed in dB.
Interchannel Gain Mismatch
With identical near full-scale inputs, the ratio of the outputs of
the two stereo channels, expressed in decibels.
Crosstalk
Ratio of response on one channel with a grounded input to a
full-scale 1 kHz sine wave input on the other channel, expressed
in decibels.
Power Supply Rejection
With no analog input, the signal present at the output when a
300 mV p-p signal is applied to power supply pins, expressed
in decibels of full scale.
Group Delay
Intuitively, the time interval required for an input pulse to
appear at the converter’s output, expressed in milliseconds (ms).
More precisely, the derivative of radian phase with respect to
radian frequency at a given frequency.
SIF Input Isolation
The level of the crosstalk between the SIF inputs in dB.
FM Limiting Sensitivity
FM limiting sensitivity is given by the modulated carrier level
that gives half the power to the FM demodulator’s output
amplitude comparing to that when the carrier level satisfies
the demodulator’s limiting level.
Deviation Mode
In some regions, the transmitted signal can deviate from the
specification. In order for the ADAV4622 to decode these high
deviation signals correctly, the appropriate modulation level
must be selected.
AM Rejection Ratio
AM rejection ratio is given by the ratio of FM (deviation = 54%)
demodulated audio level vs. residual AM (modulation = 27%)
demodulated audio level at the same carrier level. It is the ability
of the receiver to not mistake an AM signal for an FM signal.
AM Sensitivity
AM sensitivity is a measure of how well the receiver picks up
very weak AM signals.