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PCM1798 always outputs full scale

Other Parts Discussed in Thread: PCM1798, NE5534

Hi, I have implemented exactly the measurement circuit in figure 23 of the PCM1798 data sheet (SLES102A, page 18). However, when I try to give an I2S input, the output pins (17,18, 25, 26) go immediately to their maximum current values:

-the IOUTp pins [17,25] go to –5.5mA which corresponds to 800000 (–FS)

-the IOUTn pins [18, 26] go to –5.5mA which corresponds to 7FFFFF (+FS)

Please recommend what steps I should take first in order to debug this problem.  I have already tried changing the IC twice, so I think I have eliminated the possibility that I had a broken IC.

Thank you,