CS4294 datasheet(39/42 Pages) CIRRUS

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CS4294

DS326PP4

Frequency Response (FR)

FR is the deviation in signal level verses frequency. The 0 dB reference point is 1 kHz. The

amplitude corner, Ac, lists the maximum deviation in amplitude above and below the 1 kHz

reference point. The listed minimum and maximum frequencies are guaranteed to be within the

Ac from minimum frequency to maximum frequency inclusive.

Dynamic Range (DR)

DR is the ratio of the RMS full-scale signal level divided by the RMS sum of the noise floor,

in the presence of a signal, available at any instant in time (no change in gain settings between

measurements). Measured over a 20 Hz to 20 kHz bandwidth with units in dB FS A.

Total Harmonic Distortion plus Noise (THD+N)

THD+N is the ratio of the RMS sum of all non-fundamental frequency components, divided by

the RMS full-scale signal level. It is tested using a -3 dB FS input signal and is measured over

a 20 Hz to 20 kHz bandwidth with units in dB FS.

Signal to Noise Ratio (SNR)

SNR, similar to DR, is the ratio of an arbitrary sinusoidal input signal to the RMS sum of the

noise floor, in the presence of a signal. It is measured over a 20 Hz to 20 kHz bandwidth with

units in dB.

Interchannel Isolation

The amount of 1 kHz signal present on the output of the grounded AC-coupled line input

channel with 1 kHz, 0 dB, signal present on the other line input channel. Units in dB.

Interchannel Gain Mismatch

For the ADCs, the difference in input voltage to get an equal code on both channels. For the

DACs, the difference in output voltages for each channel when both channels are fed the same

code. Units in dB.

PATHS

A-D: Analog in, through the ADC, onto the serial link.

D-A: Serial interface inputs through the DAC to the analog output.

A-A: Analog in to Analog out (analog mixer).

10. REFERENCES

Intel, Audio Codec ‘97 Component Specification, Revision 2.1, May 22,1998.

http://developer.intel.com/pc-supp

/platform/ac97/

CS4294 数据表(PDF) 39 Page - Cirrus Logic