Author Topic: Have tons of 27c020, but project calls for a 27c010.  (Read 948 times)

0 Members and 1 Guest are viewing this topic.

Offline Mp3Topic starter

  • Frequent Contributor
  • **
  • Posts: 361
  • Country: us
Have tons of 27c020, but project calls for a 27c010.
« on: February 08, 2018, 07:58:15 am »
Will it work if i cut off pin 30 after programming, and double the 27c010 image to fill the missing space on the ROM?
High school graduate
 

Offline BrianHG

  • Super Contributor
  • ***
  • Posts: 7661
  • Country: ca
Re: Have tons of 27c020, but project calls for a 27c010.
« Reply #1 on: February 08, 2018, 08:20:45 am »
No need to cut the pin, just make sure it's tied to GND and you only need to fill the first half.
If the pin is tied to VCC, you only need to fill the second half.
If the pin is tied to a processor address line, you may need to fill both half with a copy of each other.

Do not leave the pin open or just cut.  This isn't good for CMOS IC inputs.
 
The following users thanked this post: Mp3

Offline james_s

  • Super Contributor
  • ***
  • Posts: 21611
  • Country: us
Re: Have tons of 27c020, but project calls for a 27c010.
« Reply #2 on: February 09, 2018, 07:59:02 am »
Double up the image either way, that will save the effort of worrying about whether the extra pin is high or low. Then you can tie it to either one, or tie it to the adjacent address pin, it will work either way.
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf