LH540203D SHARP [Sharp Electrionic Components], LH540203D Datasheet - Page 5

• Manufacturer Part Number: LH540203D
• Description: CMOS 2048X9 ASYNCHRONOUS FIFO
• Manufacturer: SHARP [Sharp Electrionic Components]

CMOS 2048
OPERATIONAL MODES
Standalone Configuration
application, the LH540203 is placed in standalone mode
by tying the Expansion In input (XI) to ground. This
input is internally sampled during a reset operation. (See
Table 1.)
DATA IN
D
When depth cascading is not required for a given
0
- D
17
FULL FLAG
RESET
WRITE
18
9 Asynchronous FIFO
FULL FLAG
DATA IN
D
WRITE
RESET
0
9
- D
W
FF
RS
Figure 5. FIFO Word-Width Expansion (2048 18)
8
LH540203
Figure 4. Standalone FIFO (2048 9)
9
W
FF
RS
XI
HF
R
RT
9
LH540203
HF
XI
9
W
RS
Width Expansion
tiple LH540203 devices in parallel. Each LH540203
should be configured for standalone mode. In this ar-
rangement, the behavior of the status flags is identical for
all devices; so, in principle, a representative value for
each of these flags could be derived from any one device.
In practice, it is better to derive ‘composite’ flag values
using external logic, since there may be minor speed
variations between different actual devices. (See Figures
4, 5, and 6.)
Word-width expansion is implemented by placing mul-
LH540203
RT
EF
9
R
XI
HF
DATA OUT
READ
EMPTY FLAG
RETRANSMIT
EF
R
RT
9
Q
0
- Q
8
EMPTY FLAG
RETRANSMIT
READ
18
DATA OUT
Q
LH540203
0
- Q
540203-17
540203-18
17
5