SN74LV138A: Enable and select input

Hi Cedrick,

Cedrick said:

1. We would like to know how the enable/select inputs are protected internally.

The inputs have a negative clamp diode, as indicated in the absolute maximum ratings table above.

The diode is indicated by the input clamp current rating, and because this rating is only valid for V_I < 0 it indicates a negative side diode only.

All pins are rated for ESD as described on the front page (above).

Cedrick said:

2. Also what happens if the enable pins are left floating?

These two FAQ's should help clear it up:

[FAQ] How does a slow or floating input affect a CMOS device? - Logic forum - Logic - TI E2E support forums

[FAQ] What is a floating input or floating node? - Logic forum - Logic - TI E2E support forums