XRT8001 Datasheet, PDF (6/48 Pages) Exar Corporation – WAN Clock for T1 and E1 Systems

XRT8001
AC ELECTRICAL CHARACTERISTICS (See Figure 4.)
Symbol
Parameter
Min. Typ. Max. Units
Conditions
t1 Input Frequency
t2 Minimum Input Signal “High” to
“Low” Duration
t3 Output Frequency
t6¹ Duty Cycle
t7⁴ Jitter Added 8kHz – 40kHz
t7⁴ Jitter Added 10Hz – 40kHz
t7⁴ Broadband Jitter
t7⁴ Jitter Added 20Hz – 100kHz
t7⁴ Jitter Added 18kHz – 100kHz
t8 Capture Time
t9 Clock Output Rise Time
t10 Clock Output Fall Time
t11² SYNC Output Signal Duty Cycle
t12 SYNC Ouput Signal + ½ Cycle
t13 SYNC Output Signal – ½ Cycle
t14 Delay Time between the rising
edge of of SYNC and the Rising
edge of CLK1 and CLK2
t21 CSB Low to Rising Edge of SCLK
Setup Time
0.008
0.008
12
32.7
32.7
MHz 3.3V
MHz 5V
ns
56
16,384 kHz
47.5 50 52.5 % VCC/2 switch point, 30pF Load
0.01 0.02 UI 3.3V, Output = 1.544MHz (0.025 UI)³
0.01 0.02 UI 5V, Output = 1.544MHz (0.025 UI)³
0.03
UI 3.3V, Output = 1.544MHz (0.025 UI)³
0.03 –
UI 5V, Output = 1.544MHz (0.025 UI)³
0.03 0.05 UI 3.3V, Output = 1.544MHz (0.05 UI)³
0.035 0.05 UI 5V, Output = 1.544MHz (0.05 UI)³
0.07 UI 3.3V, Output = 2.048MHz (1.5 UI)³
0.01 0.07 UI 5V, Output = 2.048MHz (1.5 UI)³
0.03 UI 3.3V, Output = 2.048MHz (0.2 UI)³
0.007 0.03 UI 5V, Output = 2.048MHz (0.2 UI)³
40 ms 3.3V
40 ms 5V
10ns ns 30pF load measured at 20/80%
10ns ns 30pF load measured at 20/80%
40
60 % VCC/2 switch point
t-20
t+20 ns See Table 8 for values of “t”
50
ns
t22 CSB High to Rising Edge of SCLK
20
ns
Hold Time
t23 SDI to Rising Edge of SCLK Setup Time 50
ns
t24 SDI to Rising Edge of SCLK Hold Time 50
ns
t25 SCLK “Low” Time
240
ns
t26 SCLK “High” Time
240
ns
t27 SCLK Period
500
ns
t28 CSB Low to Rising Edge of SCLK
50
ns
Hold Time
t29 CSB “Inactive” Time
250
ns
t30 Falling Edge of SCLK to SDO Valid Time
200 ns
t31 Falling Edge of SCLK to SDO Invalid Time
t32 Falling Edge of SCLK, or rising edge
of CSB to High Z
100 ns
100
ns
t33 Rise/Fall time of SDO Output
40 ns
PW_MIN F_IN Duty Cycle
12
ns
Notes:
1 _{t6 =} t4
(t4 + t5)
2 _{t11 =} ^t12
(t12 + t13)
3 _{Specifications from AT&T Publication 62411 and ITU-T}
Recommendations G-823 (for 1.544MHz and (2.048MHz).
4 _{t7 is guaranteed by characterization, not tested.}
Rev. 1.01
6