R31DS0112EU0107 Rev.1.07

Page 13

Dec 13, 2024

9FGL02x1/04x1/06x1/08x1D Datasheet

Avg. Clock Period Accuracy

TPERIOD_AVG

9FGL0xxx devices have 0 ppm

synthesis error. -0.5% SSC. [1][7][8][9]

-

0

+2500

ppm

-0.25% SSC

-

0

+1250

Absolute Period

TPERIOD_ABS

Includes jitter and spread spectrum

modulation. [1][10]

9.95

10

10.0503

ns

Jitter, Cycle to Cycle [1]

tjcyc-cyc

-

16

50

ps

Voltage High [3]

VHIGH

Statistical measurement on single-

ended signal using oscilloscope math

function (scope averaging on).

660

790

850

mV

Voltage Low [3]

VLOW

-150

-4

150

mV

Absolute Maximum Voltage

[3][11][12]

VMIN

Measurement on single-ended signal

using absolute value (scope averaging

off).

-

832

1150

mV

Absolute Minimum Voltage

[3][12][13]

VMAX

-300

-61

-

mV

Duty Cycle [1]

tDC

45

48.6

55

%

Slew Rate Matching [3][14]

ΔTrf

Single-ended measurement.

-

9

20

%

Skew, Output to Output [1]

tsk3

Averaging on, VT = 50%.

-

32

50

ps

1. Measured from differential waveform.

2. Measured from -150mV to +150mV on the differential waveform (derived from REFCLK+ minus REFCLK-). The signal must be

monotonic through the measurement region for rise and fall time. The 300mV measurement window is centered on the differential zero

crossing.

3. Measured from single-ended waveform.

4. Measured at crossing point where the instantaneous voltage value of the rising edge of REFCLK+ equals the falling edge of REFCLK-.

5. Refers to the total variation from the lowest crossing point to the highest, regardless of which edge is crossing. Refers to all crossing

points for this measurement.

6. Defined as the total variation of all crossing voltages of Rising REFCLK+ and Falling REFCLK-. This is the maximum allowed variance

in VCROSS for any particular system.

7. Refer to Section 8.6.2 of the PCI Express Base Specification, Revision 5.0 for information regarding PPM considerations.

8. PCIe Gen1 through Gen4 specify ±300ppm frequency tolerances. PCIe Gen5 reduces the allowable tolerance to ±100ppm without

spread spectrum.

9. “ppm” refers to parts per million and is a DC absolute period accuracy specification. 1ppm is 1/1,000,000th of 100.000000MHz exactly

or 100Hz. For 100ppm, then we have an error budget of 100Hz/ppm × 100ppm = 10kHz. The period is to be measured with a frequency

counter with measurement window set to 100ms or greater. The ±100ppm applies to systems that do not employ Spread Spectrum

clocking, or that use common clock source. For systems employing Spread Spectrum clocking, there is an additional 2,500ppm nominal

shift in maximum period resulting from the 0.5% down spread resulting in a maximum average period specification of +2,600ppm for

Common Clock architectures. Separate Reference Clock architectures may have a lower allowed spread percentage.

10. Defines as the absolute minimum or maximum instantaneous period. This includes cycle to cycle jitter, relative ppm tolerance, and spread

spectrum modulation.

11. Defined as the maximum instantaneous voltage including overshoot.

12. At default SMBus amplitude settings.

13. Defined as the minimum instantaneous voltage including undershoot.

14. Matching applies to rising edge rate for REFCLK+ and falling edge rate for REFCLK-. It is measured using a ±75mV window centered on

the median cross point where REFCLK+ rising meets REFCLK- falling. The median cross point is used to calculate the voltage thresholds

the oscilloscope is to use for the edge rate calculations. The Rise Edge Rate of REFCLK+ should be compared to the Fall Edge Rate of

REFCLK-; the maximum allowed difference should not exceed 20% of the slowest edge rate.

15. System board compliance measurements must use the test load. REFCLK+ and REFCLK- are to be measured at the load capacitors

CL. Single-ended probes must be used for measurements requiring single ended measurements. Either single-ended probes with math

or differential probe can be used for differential measurements. Test load CL = 2pF.

Table 7. Differential Low-Power HCSL Outputs (Cont.)

Parameter

Symbol

Conditions

Minimum Typical Maximum

Unit