Jameco Electronics 2000 ユーザーズマニュアル

Figure 16-4 illustrates the sources that create memory access time delays.

The gross memory access time is 2T, where T is the clock period. To calculate the actual 
memory access time, subtract the clock to address output time, the data in setup time, and 
the clock period shortening due to the clock spectrum spreader from 2T.

clock = 29.49 MHz,

T = 34 ns,

operating voltage is 3.3 V,

bus loading is 60 pF,

address to output time = 8 ns (see Table 16-2),

data setup time = 1 ns,

the spectrum spreader is on in normal mode, resulting in a loss of 3 ns. 

The access time is given by

access time = 2T - (clock to address) - (data setup) - (spreader delay)

= 68 ns - 8 ns - 1 ns - 3 ns
=  56 ns

data out

address

memory access
time

clock period shortening

output enable

memory output enable
time

clock

data in setup time

clock to

 (early)

output

address

due to spectrum spreader