Datasheet

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SLES014B − OCTOBER 2001 − REVISED AUGUST 2002
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APPLICATION INFORMATION
PCB layout guidelines (continued)
V
DD
Digital Section Analog Section
RF Choke or Ferrite Bead
Power Supplies
+V
S
AGND −V
S
+5V
Common
Ground
Output
Circuits
PCM1606
AGND
V
CC
Figure 33. Single-Supply PCB Layout
key performance parameters measurement
This section provides information on how to measure key dynamic performance parameters for the PCM1606.
In all cases, a System Two Cascade Plus by Audio Precision or equivalent audio measurement system is used
to perform the testing.
total harmonic distortion + noise
Total harmonic distortion + noise (THD+N) is a significant figure of merit for audio D/A converters, because it
takes into account both harmonic distortion and all noise sources within a specified measurement bandwidth.
The true rms value of the distortion and noise is referred to as THD+N.
For the PCM1606 D/A converters, THD+N is measured with a full scale, 1-kHz digital sine wave as the test
stimulus at the input of the DAC. The digital generator is set to 24-bit audio word length and a sampling frequency
of 44.1 kHz or 96 kHz. The digital generator output is taken from the unbalanced S/PDIF connector of the
measurement system. The S/PDIF data is transmitted via coaxial cable to the digital audio receiver on the
DEM−DAI1606 demo board. The receiver is then configured to output 24-bit data in either I
2
S or left-justified
data format. The DAC audio interface format is programmed to match the receiver output format. The analog
output is then taken from the DAC post filter and connected to the analog analyzer input of the measurement
system. The analog input is band-limited using filters resident in the analyzer. The resulting THD+N is measured
by the analyzer and displayed by the measurement system.