• Resolved

TVS0500: additional parallel small ESD TVS diode necessary for a full ESD/Surge Protection? Parallel and series connection?

Part Number: TVS0500

Question 1:

TVS0500 up to TVS3300 series has a fine and very flat i vs. u curve characteristic for high surge currents compared to standard TVS diodes. But surge currents are "medium speed" 8/20µs and 10/1000µs pulses. But what about high speed ESD impulses in a nanosecond range? Are the TVS0500-TVS3300 series fast enough to protect also against ns ESD pulses? Datasheet do not specifiy such a ESD protection.

What about when paralleling the TVS0500-TVS3300 series with a fast small ESD TVS diode (0402-package), for example the TVS0500 parallel with a 5.5V 0402 fast ESD diode TPD1E10B06-Q1? My idea behind, the TPD1E10B06-Q1T overtakes the fast ESD impuls and the TVS0500 overtakes a longer time surge impulse protection.

Question 2:

TVS0500 up to TVS3300 series can be connected in series to result in a part with a higher clamping voltage specification, for e.g. series connection of TVS0500+TVS3300 results in a "TVS3800"?

Question 3:

TVS0500 up to TVS3300 series can be connected in parallel to result in a part with a higher clamping voltage specification, for e.g. parallel connection of TVS3300+TVS3300 results in an "extra strong TVS3300"?

Thank you

Ralf Ohmberger

  • Ralf-

    Thanks for the detailed questions! I'll address them each.

    Question 1:The Flat-Clamp TVS family of devices integrates the very fast ESD protection as well as the longer surge protection, so there is no need for an additional small ESD diode. This is listed in the datasheet as IEC61000-4-2 ESD Immunity (the standard that defines system level ESD protection), both in the features section, ESD ratings table, and description. The device will protect with no issues.

    Question 2: Your idea is correct - two of the TVS devices can indeed be placed in series with eachother to increase the breakdown voltage and enable different voltage rail protection.

    Question 3: This one is more difficult because it requires multiple devices to have identical breakdown voltages for true current sharing, which we cannot guarantee over process and temperature. Generally, we have seen low variation in breakdown voltage between devices, but we can't guarantee that the current will share between more than one device and provide a extra storng device.

    Hopefully that answers your questions. It sounds like you've looked at this closely - if you have specific application questions that are not public, feel free to email me at alec.forbes@ti.com and we can help you out.

    Thanks,
    Alec