Cirrus Logic CS5374 - Manual (Page 31)

CS5374
CS5374
31
1 / [(2.048 MHz) x (15 pF)] = 32 k
Ω. While the
size of the internal capacitor is fixed, the voltage
reference input impedance can vary with MCLK.
The voltage reference external RC filter series re-
sistor creates a voltage divider with the VREF in-
put impedance to reduce the effective applied input
voltage. To minimize gain error resulting from this
voltage divider effect, the RC filter series resistor
should be the minimum size recommended in the
voltage reference device data sheet.
7.5 VREF Accuracy
The nominal voltage reference input is specified as
2.500 V across the VREF
± pins, and all CS5374
gain accuracy specifications are measured using a
nominal voltage reference input. Any variation
from a nominal VREF input will proportionally
vary the analog full-scale gain accuracy.
Since temperature drift of the voltage reference re-
sults in gain drift of the analog full-scale amplitude,
care should be taken to minimize temperature drift
effects through careful selection of passive compo-
nents and the voltage reference device itself. Gain
drift specifications of the CS5374 do not include
the temperature drift effects of external passive
components or of the voltage reference device it-
self.