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General Category => Digital discussion => Topic started by: ScubaCap on March 03, 2008, 01:17:08 AM

Title: Interfacing ICs
Post by: ScubaCap on March 03, 2008, 01:17:08 AM
Is it so important to interface ics with one of the ways that are explained within the theory pages? Because i have many times use ics that i connect directly output to input and i did not really had a problem. Of course if i use TTL i have common 5v supply and not different for the CMOS or other.
Title: Re: Interfacing ICs
Post by: Alex on March 03, 2008, 11:56:35 AM
When you have ttl to cmos, it is important to interface them properly as in high speeds you may have malfunctions.
Generally, interface them.
Title: Re: Interfacing ICs
Post by: kam on March 03, 2008, 12:17:00 PM
Interface them no matter what. After all, under same voltage, you only need a resistor. This resistor will help both chips to function at higher speed and also they will not use so many power to drive the next chip. It is very important especially when one chip has many exits to next levels.
Title: Re: Interfacing ICs
Post by: tpone on March 04, 2008, 16:24:12 PM
Actually, interfacing with a simple resistor is important only if you drive a CMOS from a TTL (because of the logic levels of the TTL). In any other case and always when you have same voltage, interfacing is no so important.
Title: Re: Interfacing ICs
Post by: Andre on March 04, 2008, 19:16:12 PM
Yes indeed, but this supply resistor is mandatory. I do not understand how your projects work all this time. ??? ??? ???
Title: Re: Interfacing ICs
Post by: ScubaCap on March 04, 2008, 22:14:09 PM
I really did not have a clue that interfacing should take place. It just work. Of course i did not never run anything more than 1/2 or 1/3 of it's max speed so maybe that's why it worked...
Title: Re: Interfacing ICs
Post by: Supernova on March 19, 2008, 08:08:42 AM
Normal...
Title: Interfacing ICs
Post by: beatttax73 on November 16, 2009, 17:27:50 PM
went in to have a look at ASGC today. i think they have 1 ICS gun left in store
looking to get the next load before Christmas