SI53119 Datasheet, PDF (11/35 Pages) Silicon Laboratories – 19-OUTPUT PCIE GEN 3 BUFFER

Si53119
Table 7. DIF 0.7 V AC Timing Characteristics (Non-Spread Spectrum Mode)¹ (Continued)
Parameter
Symbol
CLK 100 MHz, 133 MHz
Unit
Min
Typ
Max
Voltage Low (Typ 0.7 V)^3,8,13
Maximum Voltage⁸
V_LOW
–150
15
150
mV
V_MAX
—
850
1150
mV
Minimum Voltage
V_MIN
–300
—
—
mV
Absolute Crossing Point Voltages^3,8,14,15,16
Vox_ABS
300
450
550
mV
Total Variation of Vcross Over All Edges^3,8,18
Total ∆
—
Vox
14
140
mV
Duty Cycle^3,4
DC
45
—
55
%
Maximum Voltage (Overshoot)^3,8,19
Maximum Voltage (Undershoot)^3,8,20
Ringback Voltage^3,8
V_ovs
—
V_uds
—
V_rb
0.2
—
V_High + 0.3
V
—
V_Low – 0.3
V
—
N/A
V
Notes:
1. Unless otherwise noted, all specifications in this table apply to all processor frequencies.
2. This is the time from the valid CLK_IN input clocks and the assertion of the PWRGD signal level at 1.8–2.0 V to the
time that stable clocks are output from the buffer chip (PLL locked).
3. Test configuration is Rs = 33.2 , 2 pF for 100  transmission line; Rs = 27 , 2 pF for 85  transmission line.
4. Measurement taken from differential waveform.
5. Using frequency counter with the measurement interval equal or greater than 0.15 s, target frequencies are
99,750,00 Hz, 133,000,000 Hz.
6. The average period over any 1 µs period of time must be greater than the minimum and less than the maximum
specified period.
7. Measure taken from differential waveform on a component test board. The edge (slew) rate is measured from
–150 mV to +150 mV on the differential waveform. Scope is set to average because the scope sample clock is making
most of the dynamic wiggles along the clock edge. Only valid for Rising clock and Falling CLOCK. Signal must be
monotonic through the Vol to Voh region for Trise and Tfall.
8. Measurement taken from single-ended waveform.
9. Measured with oscilloscope, averaging off, using min max statistics. Variation is the delta between min and max.
10. Measured with oscilloscope, averaging on. The difference between the rising edge rate (average) of clock verses the
falling edge rate (average) of CLOCK.
11. Rise/Fall matching is derived using the following, 2*(Trise – Tfall) / (Trise + Tfall).
12. VHigh is defined as the statistical average High value as obtained by using the Oscilloscope VHigh Math function.
13. VLow is defined as the statistical average Low value as obtained by using the Oscilloscope VLow Math function.
14. Measured at crossing point where the instantaneous voltage value of the rising edge of CLK equals the falling edge of
CLK.
15. This measurement refers to the total variation from the lowest crossing point to the highest, regardless of which edge is
crossing.
16. The crossing point must meet the absolute and relative crossing point specifications simultaneously.
17. Vcross(rel) Min and Max are derived using the following, Vcross(rel) Min = 0.250 + 0.5 (Vhavg – 0.700), Vcross(rel)
Max = 0.550 – 0.5 (0.700 – Vhavg), (see Figures 3–4 for further clarification).
18. Vcross is defined as the total variation of all crossing voltages of Rising CLOCK and Falling CLOCK. This is the
maximum allowed variance in Vcross for any particular system.
19. Overshoot is defined as the absolute value of the maximum voltage.
20. Undershoot is defined as the absolute value of the minimum voltage.
Rev. 1.1
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