DS90UB940N-Q1: Abnormal MIPI CLK TCLK-PREPARE

Dongbao Zhou

Part Number: DS90UB940N-Q1

hello,

Could you let me know the possible reasons for the abnormal MIPI CLK TCLK-PREPARE? Customer find low probability of black screen (1/10000) for power on-off test.

Abnormal case TCLK-PREPARE>2ms, normal case TCLK-PREPARE <95ns.

Left: abnormal MIPI CLK, right: normal MIPI CLK

Dongbao

over 2 years ago

0 Ben Dattilo over 2 years ago

TI__Mastermind 25765 points

Hi Dongbao,

I cannot see any of the measurements on these images, can you post the individual images?

Is this end-to-end video, or patgen?

Is this one unit that shows the issue 1/10000 power cycles, or 1/10000 units? Can you try to recover by power cycle or digital reset?

Regards,

Ben

0 Dongbao Zhou over 2 years ago in reply to Ben Dattilo

TI__Expert 4170 points

Hi Ben,

Sorry, i don't have a high resolution waveforms on my hand, i cand confirm the only difference is the LP00 duration, abnormal one with ~2ms, normal one is <95ns.

It's power cycle test, total sample # is 5pcs. This issue could be solved by power reset or digital reset.

0 Ben Dattilo over 2 years ago in reply to Dongbao Zhou

TI__Mastermind 25765 points

Hi Dongbao,

Does this issue occur during end-to-end video or patgen? Can you have the customer see if it happens during patgen?

Please make sure the power up sequence matches what is in the datasheet.

Regards,

Ben

Interface

Interface forum

DS90UB940N-Q1: Abnormal MIPI CLK TCLK-PREPARE