Miscellaneous Pins

FILT - PLL Loop Filter Pin

A 0.22

µF capacitor should be connected from FILT to AGND.

PARAMETER DEFINITIONS

Resolution

The number of bits in the input words to the DACs, and in the output words in the ADCs.

Differential Nonlinearity

The worst case deviation from the ideal codewidth; expressed in LSBs.

Total Dynamic Range

The ratio between the DAC full scale output and the noise floor with the DAC muted. Units are

in dB.

Total Harmonic Distortion + Noise (THD+N)

THD+N is the ratio of the rms value of the input signal to the rms sum of all other spectral

components within the measurement bandwidth (10Hz to 20kHz). THD+N is expressed in dB.

Total Harmonic Distortion (THD)

THD is the ratio of the test signal amplitude to the rms sum of all the in-band harmonics of the

test signal.

Instantaneous Dynamic Range

The S/(N+D) with a 1kHz, -60dB input signal, with 60dB added to compensate for the small

input signal. Use of a small input signal reduces the harmonic distortion components of the

noise to insignificance. Units are in dB.

Interchannel Isolation

The amount of 1kHz signal present on the output of the grounded input channel with 1kHz,

0dB signal present on the other channel. Units are in dB.

Interchannel Gain Mismatch

For the ADCs, the difference in input voltage that generates the full scale code for each

channel. For the DACs, the difference in output voltages for each channel with a full scale

digital input. Units are in dB.

Frequency Response

Worst case variation in output signal level versus frequency over 10Hz to 20kHz. Units in dB.

Offset Error

For the ADCs, the deviation in LSB’s of the output from mid-scale with the selected input

grounded. For the DAC’s, the deviation of the output from zero with mid-scale input code.

Units are in volts.

CS4225

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DS86PP8