Extra 4 or 2 bits if 32/16 bits are used in x36/x18 part.

Question: what do I do with the extra 4 or 2 bits if I want to use only 32/16 bits in a X36/X18 part?

 

Answer:

Some layouts do have a problem of interfacing the SRAM to a standard DSP or a processor which uses only 16/32 bits. In these cases, the extra 4/2 bits have to be tied to a LOW or a HIGH value through individual resitors. These resistors could be 10K ohms or other high values. If the extra bits are not used for parity checking better to tie them to a HIGH or a LOW.