Hey,
I'm putting together a USB audio interface using an XHRA-2HPA device. Couple of questions:
(1) When the part is held in reset, are any of the QSPI pins tristated? I'm hoping to program the flash in-situ after assembly.
(2) When switching MCLK sources, are there any concerns about glitches - eg. can I "hard switch" between two oscillators with a multiplexer, or should I ensure a clean switch somehow?
Thanks!
XHRA-2HPA - A few implementation questions
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gmarsh
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Ross
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Yep, tri-stated (with pull-downs enabled)gmarsh wrote:Hey,I'm putting together a USB audio interface using an XHRA-2HPA device. Couple of questions:(1) When the part is held in reset, are any of the QSPI pins tristated? I'm hoping to program the flash in-situ after assembly.
Hard switch, with a delay before configuring your DAC I would recommend. Also use an external mute circuit and/or DACs internal anti-pop procedures.gmarsh wrote: (2) When switching MCLK sources, are there any concerns about glitches - eg. can I "hard switch" between two oscillators with a multiplexer, or should I ensure a clean switch somehow?Thanks!