72235LB15PF IDT, 72235LB15PF Datasheet - Page 14

• Manufacturer Part Number: 72235LB15PF
• Description: FIFO
• Manufacturer: IDT

Specifications of 72235LB15PF

• Part # Aliases: IDT72235LB15PF

OPERATING CONFIGURATIONS
SINGLE DEVICE CONFIGURATION
when the application requirements are for 256/512/1,024/2,048/4,096 words
WIDTH EXPANSION CONFIGURATION
signals of multiple devices. Status flags can be detected from any one device.
The exceptions are the Empty Flag and Full Flag. Because of variations in skew
between RCLK and WCLK, it is possible for flag assertion and deassertion to
vary by one cycle between FIFOs. To avoid problems the user must create
NOTE:
1. Do not connect any output control signals directly together.
IDT72205LB/72215LB/72225LB/72235LB/72245LB CMOS SyncFIFO
256 x 18, 512 x 18, 1,024 x 18, 2,048 x 18 and 4,096 x 18
A single IDT72205LB/72215LB/72225LB/72235LB/72245LB may be used
Word width may be increased simply by connecting together the control
DATA IN (D)
WRITE CLOCK (WCLK)
WRITE ENABLE (WEN)
LOAD (LD)
PROGRAMMABLE (PAE)
HALF FULL FLAG (HF)
FULL FLAG (FF)
WRITE CLOCK (WCLK)
WRITE ENABLE (
LOAD (
DATA IN (D
FULL FLAG (
PROGRAMMABLE (
HALF-FULL FLAG (
Figure 19. Block Diagram of Single 256 x 18, 512 x 18, 1,024 x 18, 2,048 x 18, 4,096 x 18 Synchronous FIFO
36
)
0
- D
18
)
17
Figure 20. Block Diagram of 256 x 36, 512 x 36, 1,024 x 36, 2,048 x 36, 4,096 x 36
)
Synchronous FIFO Memory Used in a Width Expansion Configuration
)
)
)
FF
FIRST LOAD (
72205LB
72215LB
72225LB
72235LB
72245LB
RESET (RS)
WRITE EXPANSION IN (WXI)
READ EXPANSION IN (RXI)
EF
)
FIRST LOAD (FL)
18
72205LB
72215LB
72225LB
72235LB
72245LB
14
IDT
18
or less. These FIFOs are in a single Device Configuration when the First Load
(FL), Write Expansion In (WXI) and Read Expansion In (RXI) control inputs
are grounded (Figure 19).
composite flags by ANDing the Empty Flags of every FIFO, and separately
ANDing all Full Flags. Figure 20 demonstrates a 36-word width by using two
IDT72205LB/72215LB/72225LB/72235LB/72245LBs. Any word width can
be attained by adding additional IDT72205LB/72215LB/72225LB/72235LB/
72245LBs. Please see the Application Note AN-83.
TM
FF
RESET (
WRITE EXPANSION IN (
RESET (RS)
72205LB
72215LB
72225LB
72235LB
72245LB
READ EXPANSION IN (
READ CLOCK (RCLK)
READ ENABLE (
OUTPUT ENABLE (
DATA OUT (Q
EMPTY FLAG (
PROGRAMMABLE (
)
EF
18
PROGRAMMABLE (PAF)
0
OUTPUT ENABLE (OE)
- Q
READ CLOCK (RCLK)
READ ENABLE (REN)
COMMERCIAL AND INDUSTRIAL
)
17
DATA OUT (Q)
)
)
)
)
)
)
EMPTY FLAG (EF)
TEMPERATURE RANGES
2766 drw 21
2766 drw 22
MARCH 2013
36