Author Topic: S-PDIF receiver converter/DAC without clock  (Read 604 times)

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Offline ricko_ukTopic starter

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S-PDIF receiver converter/DAC without clock
« on: June 10, 2020, 01:29:09 pm »
Hi,
is there such such thing as a S-PDIF receiver that converts the optical signal to analog (i.e. the DAC part) that does not  use clock? I am thinking to try to put said receiver inside a Faraday cage where the space needs to be as quiet as possible so definitely no clock/switching sources inside there.

Thank you :)
 

Offline tggzzz

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Re: S-PDIF receiver converter/DAC without clock
« Reply #1 on: June 10, 2020, 01:42:52 pm »
If you have digital signals, you have switching and switching transients. Those transients may be coupled to other circuits.

Roughly speaking, the energy in a transient depends on the transient's transition time and the change in voltage/current. So to minimise transient energy, have a balanced signal and maximise the transition time. The latter is one reason many ADCs/DACs have two outputs, one the inverse of the other.

The power in the transients can be measured over many transient periods (e.g. clock cycles), and is proportional to the frequency at which the transients occur. The power may or may not be relevant in your system.

Depending on your system, it may be possible to avoid transients during a measurement period and have the transients when no measurements are being made.
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Online David Hess

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Re: S-PDIF receiver converter/DAC without clock
« Reply #2 on: June 10, 2020, 06:51:05 pm »
The S/PDIF receiver phase locks a local clock to the incoming serial bit stream to recover timing for the DAC so you always have a clock.
 
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Offline Bassman59

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Re: S-PDIF receiver converter/DAC without clock
« Reply #3 on: June 10, 2020, 07:55:37 pm »
Hi,
is there such such thing as a S-PDIF receiver that converts the optical signal to analog (i.e. the DAC part) that does not  use clock?

Not if you actually want it to work.
 
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