• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 21 subscribers
  • Views 407 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.

Maximum frequency input to SN74AVC16T245

Dhaval Patel4
Prodigy 10 points
Other Parts Discussed in Thread: SN74AVC16T245, ADS4229, SN74AVC4T245

I have ADS4229 Evaluation board. ADS4229 which has outputs are at 1.8V. I am using SN74AVC16T245 to convert +1.8V to 3.3V. Sampling rate of ADC is 245.76 MHz. Clock (sinewave)which is output from ADC (clockout) as input to SN74AVC16T245 to convert it to 3.3V.

When input clock frequency or sampling rate  is less than 150 MHz it is working fine. When input clock frequency is 245.76 MHz, clockout from ADC is fine but output of SN74AVC16T245 is distorted.

So what is maximum frequency as input can be used with SN74AVC16T245 ?

What are other solutions I can used if SN74AVC16T245 not able to handle frequency higher that 150 MHz ?

Thanks.

  • 0
    TI__Mastermind 30310 points

    Dhaval,

    I would suggest that this part will not operate at 245.76MHz based on 2 criteria:

    1) The recommended operating condition for input rise or fall time is 5ns/V, which even for 1.2V would translate to only 83.3MHz at best, not account the different voltage levels. (this is the max recommended)

    2) The max data rate is 380mbps from 1.8 to 3.3V based on the SN74AVC4T245 datasheet, which if you are looking at a full clock period would be half the frequency, or 190MHz (this is the max tested in characterization)

    Unfortunately, all of the 16-bit translators will be spec'd in a similar fashion so I cannot recommend a faster part.

    Regards,

    Brian

  • 0
    Guru 22270 points

    You could try rolling your own highspeed level translator using a transistor or a MOSFET.  There are examples on the Internet just search for different level shifting techniques.  You may find one that suits your needs.

    Thanks,