Functional Description
Single Device Mode
A single M672061H may be used when the application requirements are for 16384
words or less. The M672061H is in a Single Device Configuration when the Expansion In (XI)
control input is grounded (see Figure 3). In this mode the Half-Full Flag (HF), which is an active
low output, is shared with Expansion Out (XO).
Figure 3. Block Diagram of Single 16384 × 9
HF
(HALF-FULL FLAG)
(W)
(R)
(Q)
READ
WRITE
HF
9
9
DATAOUT
DATAIN
(I)
(EF)
(RT)
EMPTY FLAG
RETRANSMIT
FULL FLAG (FF)
(RS)
RESET
EXPANSIONIN(XI)
M672061H
Width Expansion Mode
Word width may be increased simply by connecting the corresponding input control sig-
nals of multiple devices. Status flags (EF, FF and HF) can be detected from any device.
Figure 4 demonstrates an 18-bit word width by using two M672061H. Any word width can be
attained by adding additional M672061H.
Figure 4. Block Diagram of 16384 bits x 18 FIFO Memory Used in Width Expansion Mode
Note:
Flag detection is accomplished by monitoring the FF, EF and the HF signals on either (any) device used in the width expansion
configuration. Do not connect any output control signals together.
6
M672061H
4144K-AERO-04/07
ATMEL [ ATMEL ]
