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S/PDIF

Receiver

Evaluation Board

DEM-DAI1609A

PCM1609A(1)

2nd-Order

Low-Pass

Filter

Band Limit

A-Weight

Filter(1)

Analyzer

and

Display

Digital

Generator

S/PDIF

Output

0% Full-Scale,

Dither Off (SNR)

–60 dB FS,

1-kHz Sine Wave

(Dynamic Range)

rms Mode

HPF = 22 Hz

LPF = 22 kHz

Option = A-Weighting(2)

B0063-03

f–3 dB = 54 kHz

fC = 1 kHz

Notch Filter

IDLE-CHANNEL SIGNAL-TO-NOISE RATIO (SNR)

PCM1609A

SLES145B – AUGUST 2005 – REVISED MARCH 2008

(1)

Infinite-zero-detect mute disabled

(2)

Results without A-weighting are approximately 3 dB worse.

Figure 40. Test Setup for Dynamic Range and SNR Measurements

The SNR test provides a measure of the noise of the DAC. The input to the DAC is in all-0s data, and the DAC

infinite-zero-detect mute function must be disabled (default condition at power up for the PCM1609A). This

ensures that the delta-sigma modulator output is connected to the output amplifier circuit so that idle tones (if

present) can be observed at the output. The dither function of the digital signal generator must also be disabled

to ensure an all-0s data stream at the input of the DAC.

The measurement setup for SNR is identical to that used for dynamic range, with the exception of the input

signal level (see the notes in Figure 40).

Copyright © 2005–2008, Texas Instruments Incorporated

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Product Folder Link(s): PCM1609A