DS90UB953-Q1: Consideration of I2C speed calculation.

Harry Shin1

Hi team

When I support customer for I2C speed of UB953, I have question in datasheet description.

as data sheet, it needs to consider 38.1ns as an unit for SCL high/low time calculation.

if customer use synchronous mode/25MHz osc, this unit also is also changed to 40ns from 38.1ns?? or it always 381ns as a unit??

Thank you.

0 Harry Shin1 over 5 years ago

I missed 1more question.

I understand that SER needs to be set only SCL high/low time only,

but DES need to be set not only SCL high/low time but also I2C master enable register.

Am I correct??

Thanks

0 Ben Dattilo over 5 years ago

Hi,

I will look into this and get back to you soon.

Regards,

Ben

0 Ben Dattilo over 5 years ago

Hello,

When in synchronous mode, the unit will be changed to 40ns.

Also, the I2C master enable register only needs to be set if the DES is being used as a local I2C master.

Regards,

Ben

0 Harry Shin1 over 5 years ago in reply to Ben Dattilo

Thank you Ben. I am clear on this.

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