IDT72T72115 Integrated Device Technology, IDT72T72115 Datasheet - Page 51

• Manufacturer Part Number: IDT72T72115
• Description: 128k X 72 Terasync Fifo, 2.5v - Best Value!
• Manufacturer: Integrated Device Technology

OPTIONAL CONFIGURATIONS
WIDTH EXPANSION CONFIGURATION
signals of multiple devices. Status flags can be detected from any one device.
The exceptions are the EF and FF functions in IDT Standard mode and the IR
and OR functions in FWFT mode. Because of variations in skew between RCLK
and WCLK, it is possible for EF/FF deassertion and IR/OR assertion to vary
by one cycle between FIFOs. In IDT Standard mode, such problems can be
NOTES:
1. Use an AND gate in IDT Standard mode, an OR gate in FWFT mode.
2. Do not connect any output control signals directly together.
3. FIFO #1 and FIFO #2 must be the same depth, but may be different word widths.
IDT72T7285/72T7295/72T72105/72T72115 2.5V TeraSync™ ™ ™ ™ ™ 72-BIT FIFO
16,384 x 72, 32,768 x 72, 65,536 x 72, 131,072 x 72
Word width may be increased simply by connecting together the control
GATE
(1)
FIRST WORD FALL THROUGH/
DATA IN
SERIAL INPUT (FWFT/SI)
SERIAL CLOCK (SCLK)
PARTIAL RESET (PRS)
MASTER RESET (MRS)
FULL FLAG/INPUT READY (FF/IR)
Figure 36. Block Diagram of 16,384 x 144, 32,768 x 144, 65,536 x 144 and 131,072 x 144 Width Expansion
FULL FLAG/INPUT READY (FF/IR) #2
RETRANSMIT (RT)
m + n
PROGRAMMABLE (PAF)
WRITE CLOCK (WCLK)
WRITE ENABLE (WEN)
HALF-FULL FLAG (HF)
D
0
- D
LOAD (LD)
m
m
#1
72T72105
72T72115
72T7285
72T7295
FIFO
IDT
#1
D
m+1
m
- D
Q
51
n
0
n
- Qm
avoided by creating composite flags, that is, ANDing EF of every FIFO, and
separately ANDing FF of every FIFO. In FWFT mode, composite flags can
be created by ORing OR of every FIFO, and separately ORing IR of every
FIFO.
72T7295/72T72105/72T72115 devices. D
144-bit wide input bus and Q
bus. Any word width can be attained by adding additional IDT72T7285/
72T7295/72T72105/72T72115 devices.
Figure 36 demonstrates a width expansion using two IDT72T7285/
72T72105
72T72115
72T7285
72T7295
FIFO
IDT
#2
READ CHIP SELECT (RCS)
READ CLOCK (RCLK)
n
READ ENABLE (REN)
OUTPUT ENABLE (OE)
EMPTY FLAG/OUTPUT READY (EF/OR) #2
EMPTY FLAG/OUTPUT READY (EF/OR) #1
PROGRAMMABLE (PAE)
Q
m+1
- Q
0
-Q
n
71
from each device form a 144-bit wide output
COMMERCIAL AND INDUSTRIAL
m + n
0
- D
TEMPERATURE RANGES
71
DATA OUT
from each device form a
5994 drw41
GATE
(1)