SK-AM62: LVDS is 1.8V interface in AM62x, can I use a 3.3 V LCD panel directly?

Steven Yang2

Prodigy 80 points

Part Number: SK-AM62
Other Parts Discussed in Thread: SN75LVDS83B

Hi Sir

I wonder if I can use AM62X LVDS 1.8V interface directly connect to a 3.3 V LCD panel.

If it does not work how can I do for this problem? level shift or other way.

Thanks a lot.

Steven

over 2 years ago

0 Rajashri Hazarika over 2 years ago

TI__Intellectual 1515 points

Hello Steven,

Thank you for the query

If I can use AM62X LVDS 1.8V interface directly connect to a 3.3 V LCD panel

Ans: What is 3.3V in LCD panel? Is this power supply or I/O voltage?

To connect AM62x LVDS interface and LCD panel directly, IO voltage should match at both the ends and the LCD panel should support LVDS.

Can you please tell me if you are connecting SK-AM62 starter kit to LCD panel?

Regards

Rajashri

0 Steven Yang2 over 2 years ago in reply to Rajashri Hazarika

Prodigy 80 points

Helllo Rajashri Hazarika

Thank you very much for reply. I am sorry I did not ask the right question.

I wonder the following spec (photo) for AM62X. This spec is from TI SN75LVDS83B. I could not find this part of spec from AM62X datasheet.

we would like to connect AM62X EVM to LCD panel so I have to check this part of spec. For example, what is the spec of "Steady-state common-mode output voltage" for AM62X? (Note: AM62X's VDDA_1V8_OLDI is 1.8V and SN75LVDS83B's power is 3.3V)

+1 Rajashri Hazarika over 2 years ago in reply to Steven Yang2

TI__Intellectual 1515 points

Hello Steven,

By your explanation, I am assuming that you are trying to interface the AM62 EVM to the LCD panel directly using LVDS interface? Please confirm.

SN75LVDS83B is an LVDS SerDes data transmission system where in it takes input as three (or four) data words each containing seven single-ended data bits and converts this to an LVDS serial output.
In AM62xx,two low-voltage differential signaling (LVDS) interfaces, each with four data lanes and one clock lane are already available via Open LDI Transmitters (OLDITX0 and OLDITX1).

So, it seems possible to connect AM62xx directly to LCD panel that supports LVDS without using SN75LVDS83B.

Regards

Rajashri

0 Steven Yang2 over 2 years ago in reply to Rajashri Hazarika

Prodigy 80 points

Thanks a lot

0 Rajashri Hazarika over 2 years ago in reply to Steven Yang2

TI__Intellectual 1515 points

Hello Steven,

Thank you for the note

Regards

Rajashri

+1 Kallikuppa Sreenivasa over 2 years ago in reply to Rajashri Hazarika

TI__Guru**** 157609 points

Hello Steven,

Please refer to the specs from AM65xx having similar interface. You could use this as a reference for your analysis as we check on the availability internally.

https://www.ti.com/lit/ds/symlink/am6548.pdf

Regarding the compatibility with the LVD display, if both have LVDS interface, i guess they should be compatible.

Said that, i would recommend checking with the LCD manufacturer on the compatibility or planning prototyping.

Plese refer below threads including the part number - LCD part number is LCD185.

.(13) AM625: Interfacing LCD to AM625x - Processors forum - Processors - TI E2E support forums

(+) AM625: Interfacing LCD to AM625x - Processors forum - Processors - TI E2E support forums

(+) AM625: About DSS (Display Subsystem) of AM62x - Processors forum - Processors - TI E2E support forums

(+) AM625: Possible to use two LVDS Display - Processors forum - Processors - TI E2E support forums

Regards,

Sreenivasa

+1 Kallikuppa Sreenivasa over 2 years ago in reply to Kallikuppa Sreenivasa

TI__Guru**** 157609 points

Hello Steven,

Regarding the AM62 below are the input i received and inline with the above note.

the IOs were designed to have a 1.25V common mode voltage with similar differential output swing.

The team is internally working on the specs to be included in the datasheet. We do not have a timeline for the datasheet update.

Regards,

Sreenivasa

0 Kallikuppa Sreenivasa over 2 years ago in reply to Kallikuppa Sreenivasa

TI__Guru**** 157609 points

Hello Steven,

Please note the above information and provide your thoughts as applicable. I am closing the thread.

Regards,

0 Steven Yang2 over 2 years ago in reply to Kallikuppa Sreenivasa

Prodigy 80 points

Thanks a lot.

0 Kallikuppa Sreenivasa over 2 years ago in reply to Steven Yang2

TI__Guru**** 157609 points

Hello Steven,

Noted and thank you.

Regards,

Sreenivasa