No 1.8V out VDDA_PHY_1P8 on IMX7?

[benjaminblanton]

We're bringing up a board and there appears to be no power on VDDA_PHY_1P8 or pin Y9.  The reference design leads me to believe there is a switch to turn this output on (SW_PHY_1P8), but we can't find any registers to turn it on.  Also note MIPI_PHY_SW_PDN_REQ  is set low by default.

Thanks!

[Yuri]

Hello,

  Please look at Table 5-2 in RM, the VDDD_1P0_CAP is supplied by LDO_1P0D and

the VDDA_1P8_PHY is supplied SW_PHY_1P8, and both of them are turned off in default.

Also, use the section 5.5.9.4 (Example Code 4) in RM for the PCIe power control.

Note:  based on our recommendations from the i.MX7 DataSheet(s) :

  PCIE_VPH, PCIE_VPH_RX, PCIE_VPH_TX are supplied from internal regulator VDDA_PHY_1P8

  PCIE_VP, PCIE_VP_RX, PCIE_VP_TX are supplied from internal VDDD_CAP_1P0

Have a great day,
Yuri

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[benjaminblanton]

Thanks Yuri,

We have the switch working and are seeing both 1.0 and 1.8V now, but still are not seeing a Reference Clock out.  We are using the software from the Sabre board and it works fine.  Anything we should be looking for?

Thanks!

[Yuri]

Hello,

  Please create separate thread with detailed problem description.

Regards,

Yuri.