• Resolved

TCA9517: Translator Recommendation

Part Number: TCA9517

Requirements:

  1. host side fixed at 3.3V
  2. slave side varies 1.4V to 5.5V

I'm designing an EVM. Can you confirm that TCA9517 meets these requirements? I'm concerned that the Vcca < Vccb requirement was removed from the datasheet, but is still present in the parametric search tool:

Is there another translator better suited to my application (or that you would rather promote)?

What about TCA9517A?

Thanks,

Ren

  • Hey Ren,

    " I'm concerned that the Vcca < Vccb requirement was removed from the datasheet, but is still present in the parametric search tool:"

    Our marketing team and I have been doing some datasheet changes/corrections. We have recently removed in the design portion of the datasheet where VccB must be larger than VccA.

    For this device, VccA generates a reference voltage for A side while VccB does reference for B side BUT also drives the pull down FETs on A AND B side. It would be more beneficial if VccB were larger than VccA for higher biasing but the device should still be functional if VccA were larger than VccB.

    I still advise you follow the recommended Vcc requirements:

    From this you could place host on B side and slave on A side.

    I do know there could be concern when A side is much larger than B side. In your case the worst case would be when VccB=3.3V while VccA =5.5V. I believe the ViL could be affected but ideally you should be pulling to 0.4V or lower on B side of the device.

    "What about TCA9517A?"

    Basically the same thing but has less hysteresis/noise margin and a slightly higher ViLc. I would just stick with the non A version.

    Thanks,

    -Bobby