Regarding the issue in Digital Amplifier Interface

[arumugam]

Hi,

I have an Issue in my system to interface the I2S lines interface with Digital amplifier.I have the seperate signal processing board and I'm taking the I2S,BCLK,LRCLK outputs through Buffer(74LVC244) and in AMP board the signal is mapped to I2S to PWM converter.I placed a series termination resistor as 47E in all the signal lines in AMP board.In this condition,I could not listen the audio in the speaker and when I change the BCLK resistor as 1K keeping the other resistors as 47R then I could listen the audio output.Here I'm using the single core shielded cable with the length of 30cm to interface the amp and signal processing board..

Could anyone advice me reason behind this cause?

Thanks in Advance-Arumugam.