Cypress Rambus XDR CY24271 - Manual (Page 9)

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