DS90UB927Q-Q1: COAX support

Vijay Balaji

Prodigy 130 points

Part Number: DS90UB927Q-Q1
Other Parts Discussed in Thread: DS90UB947-Q1

Hello,

DS90UB927Q supports only STP.

Kindly suggest IC for single LVDS with COAX support.

over 1 year ago

0 Hamzeh Jaradat over 1 year ago

TI__Guru** 108100 points

Hello Vijay,

Due to the US public holiday, the team is currently out of office with some members returning 1/02. Responses will be delayed during this time. Thank you for your patience.

0 Josh Baik over 1 year ago

TI__Mastermind 22946 points

Hi Vijay,

We do have DS90UB947-Q1 which can support coax and OLDI on both sides as an alternative.

Best,

Josh

0 Vijay Balaji over 1 year ago in reply to Josh Baik

Prodigy 130 points

Hi Josh,

Thanks for the reply.

Kindly provide the Power Over COAX design guidelines for DS90UB927Q and DS90UB928.

0 Josh Baik over 1 year ago in reply to Vijay Balaji

TI__Mastermind 22946 points

Hi Vijay,

You already asked regarding PoC for 927/928 (Link). Again, The DS90UB927 and DS90UB928 do not support coax configurations or Power-over-Coax.

Best,

Josh

0 Vijay Balaji over 1 year ago in reply to Josh Baik

Prodigy 130 points

Sorry Josh, its not DS90UB927, i want POC circuit for DS90UB947.

0 Josh Baik over 1 year ago in reply to Vijay Balaji

TI__Mastermind 22946 points

Hi Vijay,

Typically PoC is not implemented with these IVI (infotainment) devices but technically it could be supported much like our camera devices 953/954/960 for example. Please see app note regarding power-over-coax design guidelines for 953: SNLA272 Note that most applications for 949/948 are for driving a display screen which draws much more power than would be practical to send over PoC due to backlight, timing controller, etc. What is the power requirement for your design?

Best,

Josh

0 Vijay Balaji over 1 year ago in reply to Josh Baik

Prodigy 130 points

Hi Josh,

Power requirement will be 12V and 2A.

+1 Josh Baik over 1 year ago in reply to Vijay Balaji

TI__Mastermind 22946 points

Hi Vijay,

We don't recommend using PoC in your applications, since it seems to draw much more power. (24W)

The reason is that a PoC network needs to maintain above 1-kOhms impedance over the operating frequency range of the FPD-Link channel. Depending on the PoC network used, there are current limits because higher current will affect the impedance of the PoC network at certain frequency ranges and then cause interference on the high-speed signal being transferred. Noise on the PoC source will also affect the quality of the high-speed signal being transferred and may cause loss of LOCK.

For example, in the UB953 datasheet, there is a PoC network that is rated up to 150mA of current. If 12V is being transferred, then the max power transferred is 1.8W.

Best,

Josh

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DS90UB927Q-Q1: COAX support