• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 30 subscribers
  • Views 603 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

PCM1862: I2C min fall time spec

Mark Desmarais1
Prodigy 85 points
Part Number: PCM1862
Other Parts Discussed in Thread: OMAP-L138

Hi-

On page 12 of the spec, min fall time is specified as 20 + 0.1*Cb ns, where Cb is the capacitive load of the line. Even if I use a minimum of 20ns, my fall times are much faster (~4ns) when the I2C bus is driven from my CPU (OMAP-L138). How is this expected to work, or am I misreading the spec somehow?

Thanks

markd

  • 0
    TI__Guru 57800 points

    Hi, Mark,

    The spec from the datasheet comes directly form the definition of I²C standard. This spec exists to reduce EMI and any other transmission line effects that may occur with fast fall times. As long as the transmission line effects or EMI do not impact the transmission of SCL/SDA and the logic timing specs are followed, the device will function correctly when operating with ~4ns fall time.

    Best Regards, 

      -Diego Meléndez López
       Audio Applications Engineer