Hi experts,
I have a qeustion about I2C SCL tHigh and tLow.
Formulas for calculating the minimum values of tHigh and tLow can be found in DS.
My customer's I2C has the following settings.
- UCBRx:64
- fBRCLK:25,000,000(25MHz)
- I2C Master
For this setting, tHigh and tLow are:
tLow,MIN = tHIGH,MIN = (UCBRx/2)/fBRCLK
= 64 / 2 / 25000000
= 1.28 usec
The customer's I2C waveform is below.
Δt is 1.28usec. t1 is where SCL is 2.1V( Positive-going input threshold voltage).
Since the customer's waveform has a slow response, it is equivalent to the value of tHIGHMIN, and it is not possible to judge whether it can meet the required specifications of tHIGHMIN.
Please tell us about:
• Need a faster waveform response?
• Is there a problem with this waveform?
Best regards,
Sasaki