42
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
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
Figure 20. Serial Loading of Programmable Flag Registers (IDT Standard and FWFT Modes)
NOTE:
1. X = 14 for the IDT72T7285, X = 15 for the IDT72T7295, X = 16 for the IDT72T72105, X = 17 for the IDT72T72115.
SCLK
SEN
SI
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LD
EMPTY OFFSET
FULL OFFSET
BIT X
(1)
t
SENS
t
LDS
t
SDS
t
SENH
t
LDS
BIT X
(1)
BIT 1
t
ENH
t
LDH
t
SDH
t
SCLK
t
SCKH
t
SCKL
BIT 1
NOTES:
1. OE = LOW; RCS = LOW.
2. The timing diagram illustrates reading of offset registers with an output bus width of 72 bits.
3. The offset registers cannot be read on consecutive RCLK cycles. The read must be disabled (REN = HIGH) for a minimum of one RCLK cycle in between register accesses.
Figure 22. Parallel Read of Programmable Flag Registers (IDT Standard and FWFT Modes)
Figure 21. Parallel Loading of Programmable Flag Registers (IDT Standard and FWFT Modes)
NOTE:
1. This timing diagram illustrates programming with an input bus width of 72 bits.
WCLK
LD
WEN
D
0
- D
n
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PAE
OFFSET
PAF
OFFSET
t
DH
t
LDH
t
ENH
t
DH
t
ENH
t
LDH
t
ENS
t
LDS
t
DS
t
CLK
t
CLKH
t
CLKL
RCLK
LD
REN
Q
0
- Q
n
DATA IN OUTPUT REGISTER PAE OFFSET VALUE PAF OFFSET VALUE
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tLDH
tENH
tCLK
tCLKL
tCLKH
tA
tLDS
tLDH
tLDS
tLDH
tLDS
tENS
tENH
tENS
tENH
tENS
tA
PAE OFFSET
tA
