• State Resolved
  • Locked Locked
  • Replies 5 replies
  • Subscribers 33 subscribers
  • Views 1220 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

TCA4311A: SDA SCL volatge level compressing

Vishnuprasanth Velusamy
Prodigy 70 points
Part Number: TCA4311A
Other Parts Discussed in Thread: TXS0104E,

Hi technical Team,

I have use the Above IC for my deign.At 100Khz of frequency, the voltage level level get decreased gradually.At smaller frequency like Hz,the voltage level not get decreased.I have connected the Vcc and EN pin to 5V and Ready pin is connected to 5V through 10K resistor.And SCL IN,SDA IN,SCL OUT and SDA OUT pins. In the reference design it is connected like this,I have followed that.But at 100KHz frequency of SCL lines,the output voltage level is 2.7V.Please provide the input to move further.

Thanks,

V.Vishnuprasanth.

  • 0
    TI__Guru 62910 points
    Hello,

    It sounds like when you decrease the bit durations (i.e., by increasing the data rate), the signals may not have enough time to stabilize at their steady-state values and therefore show a reduced peak to peak level. If you could show us an oscilloscope capture of the problem then we may be able to confirm this. Typically the solution would be to decrease the capacitance on the bus (if possible) or to decrease the pull-up resistance value (which helps to speed up the rising edges of the signal). What pull-up vale are you using, and do you have an estimate for the bus capacitance? Would it be possible to share a schematic showing your I2C implementation?

    Regards,
    Max
  • 0 in reply to Max Robertson
    Prodigy 70 points

    Hi Max,
    In my design, We planed to use the rack system.In this MCU STM32fXXXX is use in one rack,the TXS0104E is use the MCU rack in order to convert the voltage level from 3.3V to 5V level of I2C lines.The another board contains switch modules work in I2C connection were the voltage buffer TCA4311A is used.This two boards are connected through the back plane board.The over all trace capacitance is 40pF.The enable is pulled to HIGH and the READY signal is pulled HIGH through 10K resistor. The pull up resistor value 10K on both input and output side.Attached the schematic K on both input and output side.Attached the schematic

  • 0 in reply to Max Robertson
    Prodigy 70 points

    Hi Max,
    In my design, We planed to use the rack system.In this MCU STM32fXXXX is use in one rack,the TXS0104E is use the MCU rack in order to convert the voltage level from 3.3V to 5V level of I2C lines.The another board contains switch modules work in I2C connection were the voltage buffer TCA4311A is used.This two boards are connected through the back plane board.The over all trace capacitance is 40pF.The enable is pulled to HIGH and the READY signal is pulled HIGH through 10K resistor. The pull up resistor value 10K on both input and output side.Attached the schematic K on both input and output side.Attached the schematic

  • 0 in reply to Max Robertson
    Prodigy 70 points

    Hi Max,
    In my design, We planed to use the rack system.In this MCU STM32fXXXX is use in one rack,the TXS0104E is use the MCU rack in order to convert the voltage level from 3.3V to 5V level of I2C lines.The another board contains switch modules work in I2C connection were the voltage buffer TCA4311A is used.This two boards are connected through the back plane board.The over all trace capacitance is 40pF.The enable is pulled to HIGH and the READY signal is pulled HIGH through 10K resistor. The pull up resistor value 10K on both input and output side.Attached the schematic

  • 0 in reply to Vishnuprasanth Velusamy
    TI__Mastermind 49410 points

    Hey Vishnuprasanth,

    Can you provide the o-scope shots of what you are talking about in your original question?

    Thanks,

    -Bobby