FPGA Clock Jitter Allowance

Calculate remaining setup-time budget for combined clock jitter after clock period, clock-to-output, combinational path delay, setup time, and skew. Use worst-case values in the same time unit.

Description

Calculate remaining setup-time budget for combined clock jitter after clock period, clock-to-output, combinational path delay, setup time, and skew. Use worst-case values in the same time unit.

FPGA Clock Jitter Allowance: Calculate remaining setup-time budget for combined clock jitter after clock period, clock-to-output, combinational path delay, setup time, and skew. Use worst-case values in the same time unit.

When to use FPGA Clock Jitter Allowance

Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Clock period (ns): Required number input.
Clock-to-output (ns): Required number input.
Path delay (ns): Required number input.
Setup time (ns): Required number input.
Adverse clock skew (ns): Required number input.

How FPGA Clock Jitter Allowance works

Calculate remaining setup-time budget for combined clock jitter after clock period, clock-to-output, combinational path delay, setup time, and skew. Use worst-case values in the same time unit. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Jitter Allowance ns: The resulting jitter allowance ns returned as a number.

Limitations and assumptions

Setup, hold, jitter, and eye estimates require a consistent timing reference and sign convention. Clock uncertainty, skew, data-dependent jitter, process-voltage-temperature corners, routing, crosstalk, and statistical margins must come from the implementation and interface specification.
Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Alternative or Complementary approaches

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

References

Timing closure — Wikipedia contributors

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