CCS/UCD3138: Does it change "35ms" to "25ms" about rejister "CLK_LOW_ TIMEOUT" ?

user5006419

Expert 1795 points

Part Number: UCD3138

Tool/software: Code Composer Studio

Does it change "35ms" to "25ms" about rejister "CLK_LOW_ TIMEOUT" ?

Because the customer's specification is 25ms .

over 7 years ago

0 Amiel Hussain over 7 years ago

TI__Expert 4070 points

An expert will answer your question shortly.

0 Yitzhak Bolurian over 7 years ago

TI__Mastermind 18370 points

CLK_LOW_TIMEOUT on all UCD3xxx devices is 35 mS and not configurable.
The timeout of 25 mS is the min and the max is defined as 35 mS as per PMBus/SMBus specification.

0 user5006419 over 7 years ago in reply to Yitzhak Bolurian

Expert 1795 points

If the product is about to be mass produced, could TI help to change the 35ms to 25ms of the register ' CLK_LOW_TIMEOUT '?

OR how can I raise CLK & DATA of the pmbus to High level ( when CLK pull low 25ms )?

Thx.

0 Yitzhak Bolurian over 7 years ago in reply to user5006419

TI__Mastermind 18370 points

As you probably know, there is no CLK_LOW_TIMEOUT register that can be configured.
The CLK_LOW_TIMEOUT is just a read only flag.

The change from 35 mS to 25 mS may be managed by use of firmware and a timer interrupt.
We can not directly sense the CLK being pulled low, no flag that indicates CLK pulled low.
But we can detect lack of progress in processing a communication frame, using the standard PMBus controller flags.
If the communication frame is "stuck" for more than 25 mS, we can assume CLK is kept low and reset the PMBus controller.

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CCS/UCD3138: Does it change "35ms" to "25ms" about rejister "CLK_LOW_ TIMEOUT" ?