EB735 - i.MX35 PDK Power Up Sequence

[g_moreno]

Hello.

The EB735 indicates that the OSC24M_VDD and OSC_AUDIO_VDD power pin connections in the i.MX35 PDK do not comply with the i.MX35 power up recommendations. Which would be the recommended power supply in the MC13892 PMIC to connect these pins to in my final board?

[JorgeRama_rezRi]

Hi Guillermo,

Both PDK and datasheet power-up sequences work fine, so you can use either one of them for your final application.

Best regards.

Jorge.

[Yuri]

IMX35 power up sequence is as following :

1) POR asserted ;

2) digital logic domain and IO power supply VDDn, NVCCx ;

3) other power supplies: PHY1_VDDA, USBPHY1_VDDA_BIAS, PHY2_VDD,

    USBPHY1_UPLLVDD, OSC24M_VDD, OSC_AUDIO_VDD, MVDD, PVDD, FUSEVDD ;

4) POR negated.

Also, according to the i.MX35 Datasheet OSC24M_VDD, OSC_AUDIO_VDD voltage should

be in range 3.0 V - 3.6 V. Typical current consumption is 1.2mA.

IMX35 PDK provides the next power up sequence :

1) VDDn (SW2 of MC13892) ;

2) NVCCx, OSC24M_VDD, OSC_AUDIO_VDD  (VGEN2 of MC13892) ;

3) DDR, NVCC_EMIx (SW4 of MC13892) ;

4) EXT 2V775 (VIOHI of MC13892), VSD_3V15 (VSD of MC13892) ;

5) USB OTG, USB PHY  (CPU) (SWBST, VUSB of MC13892) ;

6) EXT 1V3 (SW1 of MC13892) ;

7) VPLL (VPLL of MC13892) ;

8) EXT 1.8V (SW3 of MC13892) ;

So, one of solutions - to apply VSD of MC13892 to feed OSC24M_VDD, OSC_AUDIO_VDD. 

[g_moreno]

Hello Yuri,

I will connect both signals to VSD as you suggest; I guess my original plan of connecting them to VUSB would also be appropriate. Thank you very much.

Best regards,

Guillermo

[Yuri]

OK !