Hello Ahmed,
Please see as follows:
1. Can I use sgtl5000 with outside crystal oscillator to provide m-clock? if yes how to configure hardware and software?
Yes, you can use an external oscillator to provide master clock (MCLK).
The SGTL5000 can accept an external standard master clock at a multiple of the sampling frequency (i.e. 256*Fs, 385*Fs, 512*Fs). In addition, it can take non-standard frequencies and use the internal PLL to derive the audio clocks. The device supports 8 KHz, 11.025 KHz, 16 KHz, 22.5 KHz, 24 KHz, 32 KHz, 44.1 KHz, 48 KHz, and 96 KHz sampling frequencies.
Make sure that CHIP_CLK_CTRL 0x0004 register matches with the desired configuration of your external oscillator and your application requirements. Check detailed information on Table 18 of the datasheet: https://www.nxp.com/docs/en/data-sheet/SGTL5000.pdf
2. Can I made I2C configuration without present of m-clock?
No, SYS_MCLK signal should be present and stable before I2C communication.
3. If I will use the same configuration? It can be saved? Or with restart I need to configure it again?
SGTL5000 needs to be configured every time after a power-on reset.
4. The last thing can I use it without I2S as I will not use digital audio i/o or digital audio processing?
Yes, you can route the audio signal from the analog inputs to the analog outputs without the need of using I2S.
Have a great day,
Paulina
