• State TI Thinks Resolved
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 33 subscribers
  • Views 51 views
  • Users 0 members are here
Support feedback
Options
Options
Related

SN65HVD78: Driver output short circuit protection

Malkangouda Patil
Prodigy 70 points
Part Number: SN65HVD78
Other Parts Discussed in Thread: THVD1450

Tool/software:

Hi Team,

I need a confirmation ASAP.

I need to know if there is internal short circuit protection for the driver output. 

I was analyzing a situation which I am facing in my design. I am using multiple drivers on 2 different boards, what happens when the cables of two driver output are connected by mistake. 

There will be a dead short between the driver pins of both the ICs, when one driver pulls the bus high and the other pulls it low. For this type of failure cases I am hoping that there is internal short circuit current limiting in the IC on both the driver output pins.

When the IC goes into thermal shutdown the driver pins will be in high impedance state right?. Does the driver restart automatically after the fault is cleared?

I need more information on both of these failure conditions, driver output short circuit and thermal shutdown.

Please give your inputs. 

Thank you

Malkangouda Patil

  • 0
    TI__Genius 13472 points

    Hi Malkangouda,

    This device has 160mA short circuit protection. This can be seen in the Electrical Characteristics section of the datasheet (you can search for "IOS"). 

    Yes, the driver will be high-impedance during thermal shutdown:

    Once the temp range re-enters valid levels, the device will resume operation based on the /RE and DE pins. 

    Overall, this device should handle this condition fine assuming the two drivers combined current doesn't violate this device's abs max conditions. However, I would highly recommend switching to our newer THVD14xx line of devices, particularly THVD1450. This device offers essentially the same specs but with higher short circuit current protection among other improved features. Our THVD14xx line of devices has many improvements over the SN65HVDxx line of devices (improved cost structure, better ESD protection, higher bus fault protection, etc).

    Let me know if you have any other questions or if you need help selecting a transceiver. 

    Best,

    Ethan