SRC4382: Selection of SRC output sample rate

Tom Izett

Part Number: SRC4382

Hello.

I have a simple question, I hope.

In the SRC4382, how is the output sample rate from the sample-rate-converter determined?

On p.33 of the datasheet, this signal is shown as INT_SYNC, but it is not mentioned elsewhere how this signal is generated. Does it simply pick it up from the frame clock of one of the sources selected to take the SRC output?

Many thanks in advance for your help.

over 5 years ago

0 Ravi Patil over 5 years ago

TI__Expert 5645 points

Hi Tom,
Welcome to e2e Forum.

The input-to-output sampling ratio is determined automatically by the SRC rate estimation circuitry, with the digital re-sampler parameters being updated in real-time without the need for programming.

SRC receives a digital audio input from one of three data sources: Port A, Port B, or the DIR & the output of the SRC may be connected to Port A, Port B, and/or the DIT. The INT_SYNC is coming from either one of the 3 sources on the output side which determine the output sampling rate. When a change in one or both of the sampling rates occurs, the servo loop in the device enter Fast mode operation. When a servo loop has settled in Fast mode, it will then switch to Slow mode. When both the input and output servo loops have switched to Slow mode, the RDY output (pin 15) is forced low, indicating that the SRC has completed the rate estimation process.

Thanks.

Best regards,
Ravi

0 Tom Izett over 5 years ago in reply to Ravi Patil

Prodigy 20 points

Thanks Ravi, much appreciated.
I think that's what I expected from the datasheet. I suppose one just has to be sure not to try to send the SRC output to two destinations with different sample rates.

Regards,
Tom.

Because of the Thanksgiving holiday in the U.S., TI E2E™ design support forum responses may be delayed from November 25 through December 2. Thank you for your patience.

Audio

Audio forum

SRC4382: Selection of SRC output sample rate