Cypress Semiconductor Rambus XDR CY24272 Scheda tecnica - Pagina 9

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Cypress Semiconductor Rambus XDR CY24272 Scheda tecnica
AC Electrical Specification
The AC Electrical specifications follow.
Parameter
t
Clock Cycle time
CYCLE
t
Jitter over 1-6 clock cycles at 400–635 MHz
JIT(cc)
Jitter over 1-6 clock cycles at 638–667 MHz
L
Phase noise SSB spectral purity L(f) at 20 MHz offset: 400–500 MHz
20
(In addition, device must not exceed L(f) = 10log[1+(50x10
f = 1 MHz to 100 MHz except for the region near f = REFCLK/Q where Q is
the value of the internal reference divider.)
t
Cycle-to-cycle duty cycle error at 400–635 MHz
JIT(hper,cc)
Cycle-to-cycle duty cycle error at 636–667 MHz
Δt
Drift in t
when ambient temperature varies between 0°C and 70°C and
SKEW
SKEW
supply voltage varies between 2.375V and 2.625V.
DC
Long term average output duty cycle
t
PLL output phase error when tracking SSC
EER,SCC
t
,t
Output rise and fall times at 400–667 MHz (measured at 20%–80% of output
CR
CF
voltage)
t
Difference between output rise and fall times on the same pin of the single
CR,CF
device (20%–80%) of 400–667 MHz
Table 9. SMBus Timing Specification
Parameter
FSMB
SMBus Operating Frequency
TBUF
Bus free time between Stop and Start Condition
THD:STA
Hold time after (Repeated) Start Condition.
After this period, the first clock is generated.
TSU:STA
Repeated Start Condition setup time
TSU:STO
Stop Condition setup time
THD:DAT
Data Hold time
TSU:DAT
Data Setup time
TTIMEOUT
Detect clock low timeout
TLOW
Clock low period
THIGH
Clock high period
TLOW:SEXT
Cumulative clock low extend time (slave device)
TLOW:MEXT
Cumulative clock low extend time (master device)
TF
Clock/Data Fall Time
TR
Clock/Data Rise Time
TPOR
Time in which a device must be operational after power on reset
Document Number: 001-42414 Rev. **
[6]
Description
[19]
[20]
[22]
Description
Min
1.25
–
–
–
6
2.4
/f)
] –138 for
–
–
–
[21]
45%
–100
–
–
Min
10
4.7
4.0
4.7
4.0
0
250
4.7
4.0
CY24272
Typ
Max
Unit
3.34
ns
25
40
ps
25
30
ps
–135
–128
dBC/Hz
25
40
ps
25
30
ps
–
15
ps
50
55%
t
CYCLE
–
100
ps
150
–
ps
–
100
ps
Max
Units
100
kHz
μs
μs
μs
μs
ns
ns
Not supported
μs
μs
50
25
ms
CY24272 doesn't
extend
10
ms
300
ns
1000
ns
500
ms
Page 9 of 13
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