180NQ045R ATMEL Corporation, 180NQ045R Datasheet - Page 7

• Manufacturer Part Number: 180NQ045R
• Description: 45V 180A Schottky DISCR. (R) Diode in a D-67 HALF-Pak package
• Manufacturer: ATMEL Corporation

single word to be read after one word has been written to
an empty FIFO stack. The data is enabled on the bus at
(tWEF + tA) ns after the leading edge of W which is
known as the first write edge and remains on the bus until
the R line is raised from low to high, after which the bus
will go into a three-state mode after tRHZ ns. The EF line
will show a pulse indicating temporary reset and then will
be set. In the interval in which R is low, more words may
be written to the FIFO stack (the subsequent writes after
the first write edge will reset the Empty Flag) ; however,
the same word (written on the first write edge) presented
to the output bus as the read pointer will not be
incremented if R is low. On toggling R, the remaining
words written to the FIFO will appear on the output bus
in accordance with the read cycle timings.
Rev. F – June 30, 1999
Figure 4. Block Diagram of 12288 9 FIFO Memory (Depth expansion).
Figure 5. Compound FIFO Expansion.
Notes : 6. For depth expansion block see section on Depth Expansion and Figure 4.
R . W . RS
7. For Flag detection see section on Width Expansion and Figure 3.
FULL
EXPANSION
M67204E
DEPTH
BLOCK
I
0
– I
RS
W
6
8
I
0
Q
9
– I
0
8
– Q
8
Q
0
– Q
8
FF
9
FF
9
FF
9
67204E
67204E
67204E
EXPANSION
M67204E
I
M
M
M
9
DEPTH
BLOCK
In the write flow-through mode (figure 18), the FIFO
stack allows a single word of data to be written
immediately after a single word of data has been read
from a full FIFO stack. The R line causes the FF to be
reset, but the W line, being low, causes it to be set again
in anticipation of a new data word. The new word is
loaded into the FIFO stack on the leading edge of W. The
W line must be toggled when FF is not set in order to write
new data into the FIFO stack and to increment the write
pointer.
XI
– I
XO
17
FL
EF
EF
EF
FL
FL
I
9
Q
Q
– I
9
9
17
– Q
– Q
17
17
9
I
(N–8)
Q
R
– I
EXPANSION
M67204E
N
V
DEPTH
BLOCK
CC
M67204E
EMPTY
I
(N–8)
Q
Q
(N–8)
(N–8)
– I
– Q
– Q
N
N
N
7