• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 33 subscribers
  • Views 282 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.

Original question:

PCA9545A: Hot insertion feature of PCA9545A

PCA9545A: use PCA9545A at External Card side with hot insertion

Frank Xiao
Genius 12055 points
Part Number: PCA9545A
Other Parts Discussed in Thread: TCA9511A

HI team,

My customer is looking for a switch device has hot insertion function which can be used at the External Card as PCA9511. As you know PCA9511 can be used at External Card. But PCA9545A can be used at backplane card. We want to check whether we can used PCA9545 on the External Card also support hot insertion. IF NOT.  Please also help explain the details about why the PCA9545 can only be used on the backplane side, PCA9511 can only be used on the External Card side. Many thanks.

  • 0
    TI__Guru 74851 points

    Hi Frank,

    The 9545A does not have any kind of protection against bad PoR which is one of the concerns when hot plugging thing into a backplane. A bad poR can cause SDA to get locked and remain locked until the device is reset or the processor can send clock to the stuck device to try to unstick it. TCA9511A is designed to detect if there is a stuck bus upon insertion and keep the downstream components from sticking the main bus low. 

    "PCA9511 can only be used on the External Card side"

    You can use the TCA9511A on the backplane but you lose the hot insertion feature since it is no longer going through its checks to ensure that the downstream devices have poweredup properly. This is something that only occurs once during the initial insertion while TCA9511A is on the external card.

    -Bobby