IDT72T36115 Integrated Device Technology, IDT72T36115 Datasheet - Page 28

• Manufacturer Part Number: IDT72T36115
• Description: 128k X 36 Terasync Fifo, 2.5v - Best Value!
• Manufacturer: Integrated Device Technology

NOTES:
1. REN is LOW.
2. t
3. Qslowest is the data output with the slowest access time, t
4. Time, t
ECHO READ CLOCK (ERCLK)
selectable via RHSTL. The ERCLK is a free-running clock output, it will always
follow the RCLK input regardless of REN and RCS.
delay provides the user with a more effective read clock source when reading
data from the Qn outputs. This is especially helpful at high speeds when
variables within the device may cause changes in the data access times. These
variations in access time maybe caused by ambient temperature, supply
voltage, device characteristics. The ERCLK output also compensates for any
trace length delays between the Qn data outputs and receiving devices inputs.
effect on the ERCLK output produced by the FIFO device, therefore the ERCLK
output level transitions should always be at the same position in time relative to
the data outputs. Note, that ERCLK is guaranteed by design to be slower than
the slowest Qn, data output. Refer to Figure 4, Echo Read Clock and Data
Output Relationship, Figure 28, Echo Read Clock & Read Enable Operation
and Figure 29, Echo RCLK & Echo REN Operation for timing information.
Q
IDT72T3645/55/65/75/85/95/105/115/125 2.5V TeraSync™ ™ ™ ™ ™ 36-BIT FIFO
1K x 36, 2K x 36, 4K x 36, 8K x 36, 16K x 36, 32K x 36, 64K x 36, 128K x 36 and 256K x 36
SLOWEST
ERCLK
ERCLK
The Echo Read Clock output is provided in both HSTL and LVTTL mode,
The ERCLK output follows the RCLK input with an associated delay. This
Any variations effecting the data access time will also have a corresponding
RCLK
Figure 4. Echo Read Clock and Data Output Relationship
(3)
> t
D
is greater than zero, guaranteed by design.
A
, guaranteed by design.
t
A
t
ERCLK
t
D
t
ERCLK
A
.
5907 drw08
28
ECHO READ ENABLE (EREN)
selectable via RHSTL.
output and provides the reading device with a more effective scheme for reading
data from the Qn output port at high speeds. The EREN output is controlled by
internal logic that behaves as follows: The EREN output is active LOW for the
RCLK cycle that a new word is read out of the FIFO. That is, a rising edge of
RCLK will cause EREN to go active, LOW if both REN and RCS are active, LOW
and the FIFO is NOT empty.
SERIAL CLOCK (SCLK)
on the SCLK input is used to load serial data present on the SI input provided
that the SEN input is LOW.
DATA OUTPUTS (Q
for 18-bit wide data or (Q
The Echo Read Enable output is provided in both HSTL and LVTTL mode,
The EREN output is provided to be used in conjunction with the ERCLK
During serial loading of the programming flag offset registers, a rising edge
(Q
0
-Q
35
) are data outputs for 36-bit wide data, (Q
0
-Q
n
0
)
-Q
8
) are data outputs for 9-bit wide data.
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
0
JANUARY 11, 2007
- Q
17
) are data outputs