Author Topic: 74LVC series above 3.6V Vcc ?  (Read 2473 times)

0 Members and 1 Guest are viewing this topic.

Offline westfwTopic starter

  • Super Contributor
  • ***
  • Posts: 4199
  • Country: us
74LVC series above 3.6V Vcc ?
« on: June 12, 2017, 06:34:48 am »
The 74LVC series is supposed to be 3.6V logic with 5V tolerant inputs.  But the datasheets say that the max supply voltage is 6.5V !
Can I use some 74LVC00s in a 5V system if I'm missing more appropriate logic families?  What can I expect, behavior-wise, from the high (but not too excessive) supply voltage?
 

Offline bson

  • Supporter
  • ****
  • Posts: 2270
  • Country: us
Re: 74LVC series above 3.6V Vcc ?
« Reply #1 on: June 12, 2017, 08:10:12 pm »
What mr blue said above.  LVC is also varies in its tolerance and it varies between parts, so you'll need to check the specific datasheets on this one.
 

Online Zero999

  • Super Contributor
  • ***
  • Posts: 19517
  • Country: gb
  • 0999
Re: 74LVC series above 3.6V Vcc ?
« Reply #2 on: June 12, 2017, 10:21:44 pm »
So the part is specified to work up to 3.6V but the absolute maximum voltage rating is 6.5V. . .

This means the part is guaranteed to work at 3.6V and no more. It will tolerate voltages up to 6.5V but without any guarantee it'll still conform to the other specifications such as power consumption.
« Last Edit: June 13, 2017, 07:38:12 am by Hero999 »
 

Offline Cervisia

  • Regular Contributor
  • *
  • Posts: 83
  • Country: 00
Re: 74LVC series above 3.6V Vcc ?
« Reply #3 on: June 13, 2017, 12:27:15 pm »
Please note that the single-gate LVC devices (74LVC1G00 etc.) are guaranteed to work at 5 V.

I suspect that it would be possible to use a single gate in a larger chip at 5 V, but that using multiple gates that switch at the same time would result in ground bounce large enough that the entire chip might no longer work in the worst circumstances.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf