Hi,
I recently started evaluating TAS3308 DAP. I am using a TAS3308EVM-LC. In a process flow chart, I added TAS3308ADCIn and TAS3308PWMOut blocks. I also have TAS3308AudioApp block. ADCIn is directly connected to PWMOut. When I generate code for this process flow and run the target, I can clearly hear through a headphone whatever signal I feed at Line In input connector.
There is a variable phase delay between input and output signals when measured using an oscilloscope. Input signal is measured between Pin 2 on connector J4 and GND. Output signal is measured between Tip (Left channel) on headphone socket J10 and GND.
With 50Hz sinewave as input, phase difference between Input and Output = 9ms.
At 100Hz, it is 3.5ms.
At 500Hz, it is 3.0 ms.
At 1kHz, it is .25 ms.
At 2kHz, it is .02 ms and
At 5kHz, it is .06 ms.
This variable phase delay is not noticeable when output is played through earphones, but I believe it will cause silent zones when played through a PA system and heard at longer distances from the source. Is this variable phase delay an artifact of the DAP? Is there a way to compensate for this variable delay?
Thanks,
Shyam Nallabolu