Hi,
I agree with Andy here. It is important to prevent your inputs from floating.
It is dangerous to leave input pins floating, specially if you have multiple gates and a noisy board. You will get some difficult problems to solve when you start debugging your design.
Hi,
I agree with Andy here. It is important to prevent your inputs from floating.
It is dangerous to leave input pins floating, specially if you have multiple gates and a noisy board. You will get some difficult problems to solve when you start debugging your design.
It strongly depends on I/O ports schematic of target IC. Most of modern IC have internal weak pull-down (pull-up) on all pins, so you can easy leave them unconnected and simplify task for your PCB designer.
As to any particular IC - you have ALWAYS check with its datasheet/app.notes - there is no generic answer for this question.
Yes,
That is true for a lot of ICs, but I normally connect them to the ground if they are not used, just to be safe!
And for the IOs, most of the time, I put a 10k pulup to the VCC, but in most of the designs I have been involved in, the board was for very complex devices or for hobby! In both cases, adding a few resistors or a couple of ground pins doesn't matter that much.