DS90UB947-Q1: schematic review

Dexter Choi

Expert 2795 points

Part Number: DS90UB947-Q1

Dear SIr,

Could you please review attached schematic?

Volvo AVN_MAIN_v2_1_sch.pdf

over 5 years ago

0 Vijaya Ceekala over 5 years ago

TI__Intellectual 2930 points

Hello Dexter

We will do this. Typically it will take us about 3 days to complete the schematic review

Thanks

Vijay

0 Dexter Choi over 5 years ago in reply to Vijaya Ceekala

Expert 2795 points

Dear Sir,

My customer will develop AVN using DS90UB947 and DS90UB948 as below priture.

INPUT: Single pixel 24BIT 90Mhz

OUT: Single LINK

how to select configuration MODE_SEL0 and MODE_SEL1 for DS90UB947 side?

Below is DS90UB948 configuration.

0 Hamzeh Jaradat over 5 years ago in reply to Dexter Choi

TI__Guru** 107670 points

Hello Dexter,

It looks like you are using an old datasheet. Please download the latest datasheet from here.

https://www.ti.com/product/DS90UB947-Q1

For 947 I believe you are using the MSB on Data lane 3, correct? If correct then your MAP_SEL settings shall be 00 in both tables.

0 Dexter Choi over 5 years ago in reply to Hamzeh Jaradat

Expert 2795 points

Dear Hamzeh,

You mean is setting it as like below capture?

0 Hamzeh Jaradat over 5 years ago in reply to Dexter Choi

TI__Guru** 107670 points

Hello Dexter,

If you are using the MSB on Data lane 3 and just 1x oLDI interface, then this setting is correct!

0 Dexter Choi over 5 years ago in reply to Hamzeh Jaradat

Expert 2795 points

Thank you very much!!

0 Dexter Choi over 5 years ago in reply to Dexter Choi

Expert 2795 points

Dear Hamzeh,

I have a question as below.

AC coupling CAP value of DS90UB947 are 33nF or 0.1uF with DS90UB298?

0 Hamzeh Jaradat over 5 years ago in reply to Dexter Choi

TI__Guru** 107670 points

With 928 please use 100nF.

0 Dexter Choi over 5 years ago in reply to Hamzeh Jaradat

Expert 2795 points

Dear Hamzeh,

Thank you for your reply.

Can i get schematic review comment?

please check it.

0 Hamzeh Jaradat over 5 years ago in reply to Dexter Choi

TI__Guru** 107670 points

Hello Dexter,

I have checked your schematic. Everything looks fine to me.

Just one suggestion, you may add a place holder for an CMC on DOUT+/- for improving EMI, on a system level, if needed.

0 Dexter Choi over 5 years ago in reply to Hamzeh Jaradat

Expert 2795 points

Hi Hamzeh,

you mean CMC is ceramic cap?

could you advise me detail how to add a place holder for an CMC and value?

Thanks.

0 Hamzeh Jaradat over 5 years ago in reply to Dexter Choi

TI__Guru** 107670 points

Dexter,

CMC is a Common Mode Choke. You can use the one from our reference design. This can be found in this document.

https://www.ti.com/lit/ug/snlu140a/snlu140a.pdf?ts=1592982608323&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FDS90UB947-Q1

You may add x2 0ohm resistors on the CMC footprint to have the options of using CMC or using 0 ohm.

Interface

Interface forum

DS90UB947-Q1: schematic review