SN3257-Q1: Does the floating pin will damage the device

Hello team,

We used two devices for the signal switching,and the pin 14(S4A) of one of them is not used.

After two months,we noticed that the unused one is damaged,the pins(S4A,S4B) are short-circuited to ground.

We would like to know if there is a connection between the two things.

In the 8.4 of the data sheet,I saw that "Unused signal path inputs (SxA, SxB, or Dx) should be connected to GND. "

But I cant find the more description about this.

Best,

Richard

Kailyn Chen：

Hello, usually, we didn't recommend the unused input to float in case picked up the noise.

Generally we recommend to connect VCC or GND to avoid floating.

As to the unused pin of SN3257, the datasheet also provide the description of the unused pin. 

In addition, the below application note is the about "implications of slow or floating CMOS input" which is about the logic control pin:

https://www.ti.com.cn/cn/lit/an/scba004e/scba004e.pdf