IC area for a flip-flop and SRAM?

[Weng Tianxiang]

Hi,
I want to know which has larger IC area, flip-flop and SRAM. Why? and
how many transistors are there for flip-flop or SRAM?

Weng

 

[Nahum Barnea]

shihhsin_hu@yahoo.com (Jason Hu) wrote in message news:<6deb0c1b.0405312355.3121000b@posting.google.com>...

SRAM is much smaller than FF.

SRAM has 4 or 6 transistors per bit.
FF usually has 15-20 transistors.


wtx@umem.com (Weng Tianxiang) wrote in message news:<511e4538.0405190726.9399ff7@posting.google.com>...
Hi,
I want to know which has larger IC area, flip-flop and SRAM. Why? and
how many transistors are there for flip-flop or SRAM?

Weng

This is true.
and also the sram mux is very efficient (area).

But beware that there is minmum size were it make sense to put an sram.
for 0.18 u tehnnology tsmc say:
100000 flops in 1 square milimeter (in typical case it is probably much less)
and 4.65 square micron for one sram bit.

sram requires extra logic for bist.
and there can also be problems of routing above the sram core.