DS90UB934-Q1: 934 lost lock time

Betty Guo

Part Number: DS90UB934-Q1

Hi team,

we have two questions need your help:

1. for 934, how long it will lost lock when occur unexpect ting, such as unstable clock? can we have method to measured it ?

2. about parity error, customer found the count of parity is out of threshold, what reasons will cause parity error, what condition or data belong to parity error? because we found that even the 934 work properly, we still find parity error.

thank you

over 4 years ago

0 Nicholas Darash over 4 years ago

TI__Mastermind 18755 points

Hello,

1. Are you asking how long it will take for the 934 to regain LOCK after it loses it? It really depends on the status of the AEQ circuit and how it is programmed.

2. Parity errors are errors in forward channel FPD data. To minimize the amount of parity errors you can use the MAP tool https://www.ti.com/lit/ug/snlu243/snlu243.pdf? to program the AEQ with a more optimal setting.

Regards,

Nick

0 Betty Guo over 4 years ago in reply to Nicholas Darash

TI__Expert 7300 points

Hi Nick,

1. No, I mean how long it will take from LOCK to unlock? not from unlock to lock.

2. I want to know why will parity error even in normal.

0 Nicholas Darash over 4 years ago in reply to Betty Guo

TI__Mastermind 18755 points

Hi Betty,

1. The LOCK signal represents the status of the PLL. There is not going to be any significant delay from when you are no longer receiving data to when the signal goes low.

2. If a parity error happens then there is an error in the forward channel. It can happen occasionally due to many variables but you really shouldn't be seeing them.

Regards,

Nick

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DS90UB934-Q1: 934 lost lock time