74HCT125D vs 74HCT125M help pls... - Page 1
Forum section: electronics / repair

author: Chriss
author_rank: Frequent Contributor
timestamp: July 07, 2019, 06:00:06 pm
content: Hi!I have to repair or better to say to "rework" a device which is equipped with 4pcs 74HCT125D type of IC's butsuggested from peoples from the Net these IC's should be interchanged with 74HCT125M version.I assume the mentioned "74HCT125M" version is actually a 74HC125 version which is maybe CMOS level IC...I'm searching for days on the Net for the M version but can't find nothing except stores who sell this M type parts like Aliexpress etc.I don't see does the original D type IC's are failed but peoples suggest to change them.The mentioned device under repair is a so called CAR PROG programming device.The device can not deal with eeprom's...Can somebody tell me what is the difference between the D and M type?Thank you.

author: kripton2035
author_rank: Super Contributor
timestamp: July 07, 2019, 08:20:56 pm
content: in this datasheet they talk about a M version, but I did not find the difference ?http://www.ti.com/lit/ds/symlink/cd74hct125.pdf

author: Chriss
author_rank: Frequent Contributor
timestamp: July 07, 2019, 08:29:19 pm
content: Yea, I found that too, but come to the same conclusion like you.I didn't recognized any differences.I'm thinking about the reason why people just change from D version to M version and I can't figure out any reasons...From my side, that letter D or M has nothing to do with the repairing.That peoples are just put new parts on the pcb and if one of them failed before with the old parts which was the D version,now is working. Not because of the D or M version but cos the new parts.Conclusion, changing all four parts with new D or M parts can maybe repair the unit.But strictly searching for the M version of the IC has nothing to do with the repairing.Maybe I'm wrong, but this is how I see this stuff.

author: edavid
author_rank: Super Contributor
timestamp: July 07, 2019, 08:33:25 pm
content: D and M are package suffixes, which are not standardized between manufacturers.D is NXP's suffix for SOIC.M is TI's suffix for SOIC.NXP 74HCT125D and TI 74HCT125M are designed to be interchangeable.What these people are really telling you is that the TI part is somehow better than the NXP part, which is unlikely, but you can buy them from any TI distributor:https://www.findchips.com/search/74hct125m

author: wraper
author_rank: Unknown
timestamp: July 07, 2019, 08:33:36 pm
content: Both are just suffix to indicate SO package used by different manufacturers.

author: Chriss
author_rank: Frequent Contributor
timestamp: July 07, 2019, 08:40:37 pm
content: Thank you guys, you are helped me to be sure does that peoples are do some "rework" but have no clue what the do...D or M are the same device as you told, and as I figured out also but I was not sure does I missing something.Problem solved I will say.Thanks again..

author: wraper
author_rank: Unknown
timestamp: July 07, 2019, 08:42:52 pm
content: Quote from: edavid on July 07, 2019, 08:33:25 pmYou've beat me by 11 seconds. Though both D and M suffixes are not unique to TI and NXP. Especially if you consider manufacturers which no longer exist due to acquisition bloodbath.To OP, go against the system and use MC74HCT125ADG from ON semi.