Embedded VBIOS vs Mobile VBIOS

[Kepcoate]

Hi,

We are using using E3927 processor on a COMExpress module. The COM module has eDP to LVDS converter. The LVDS link does not work with Embedded VBIOS but works with Mobile VBIOS. The issue is  that the eDP to LVDS converter part from Realtek supports 1.4 version and hence need 200mV signalling. But the E3927 is putting out 400mV signalling with Embedded BIOS. But when the OEM of the module switched it to Mobile VBIOS they get 200mV signalling and everything works.

We are not sure if this is the right solution to the problem. Can you please help us in understanding the difference in Embedded and Mobile VBIOS and what impact this can have on the design?

Thanks

[Diego_INTEL]

Hello @Kepcoate,

Thank you for contacting Intel Embedded Community.

The active support for Apollo Lake family has ended on September 30.

Regarding your consultation, the Apollo Lake documentation mentions that it supports eDP 1.3, that I understand it works at 400 mV, while 1.4 works at 200 mV, it doesn't mention that supports 1.4 but doing this works, so it should be fine.

I looked for details regarding those options but didn't find much, so I'm thinking that the mobile options set the interface for small devices while embedded to the full capacity as it can support bigger screens.

The workaround seems fine at least.

Best regards,

@Diego_INTEL