Silicon Pr0n

User Tools

Site Tools

Trace: • components • sbt • determining_pinout • fpga
determining_pinout

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision		Previous revision
determining_pinout [2012/03/02 07:20] – mcmasterdetermining_pinout [2013/10/20 14:59] (current) – external edit 127.0.0.1
Line 15: Line 15:
 {{gallery>:mcmaster:pmos_nmos_sizes.jpg}} {{gallery>:mcmaster:pmos_nmos_sizes.jpg}}
  
-Notice that the right side is larger?  This means that the right side is PMOS and the left side is NMOS.  Since NMOS likes to connect to ground and PMOS likes to connect to V+ the right side is V+ and the left side is V-.  This can then be traced as needed.+Notice that the left side is smaller than the right?  This means that the left side is NMOS and the right side is PMOS.  Since NMOS on the left likes to connect to ground (V-) and PMOS on the right likes to connect to power (V+) we have identified the power nets.  This can then be traced as needed.
  
 If the cells are matched size or its a specialized chip you might not have this luxury.  In that case start looking for connections to ground rings.  For example, in this chip power pins are very distinctive because the protection network is very different, it feeds directly to the power ring around the chip, and the input is a lot larger: If the cells are matched size or its a specialized chip you might not have this luxury.  In that case start looking for connections to ground rings.  For example, in this chip power pins are very distinctive because the protection network is very different, it feeds directly to the power ring around the chip, and the input is a lot larger:
determining_pinout.1330672813.txt.gz · Last modified: 2013/10/20 14:59 (external edit)