Bathtub Failure Rate Model
Evaluate a simple bathtub-shaped hazard model: early exponential decay plus constant random-failure rate plus a Weibull wear-out term. All time parameters use the same unit; this is an illustrative model that requires fitted coefficients.
Description
Evaluate a simple bathtub-shaped hazard model: early exponential decay plus constant random-failure rate plus a Weibull wear-out term. All time parameters use the same unit; this is an illustrative model that requires fitted coefficients.
Bathtub Failure Rate Model: Evaluate a simple bathtub-shaped hazard model: early exponential decay plus constant random-failure rate plus a Weibull wear-out term. All time parameters use the same unit; this is an illustrative model that requires fitted coefficients.
When to use Bathtub Failure Rate Model
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.
- Elapsed time
- Required number input.
- Early-failure amplitude
- Required number input.
- Early decay time
- Required number input.
- Constant hazard rate
- Required number input.
- Wear-out scale
- Required number input.
- Wear-out shape
- Required number input.
How Bathtub Failure Rate Model works
Evaluate a simple bathtub-shaped hazard model: early exponential decay plus constant random-failure rate plus a Weibull wear-out term. All time parameters use the same unit; this is an illustrative model that requires fitted coefficients. 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
- Hazard Rate
- The resulting hazard rate returned as a number.
Limitations and assumptions
- A constant failure rate or FIT conversion applies only within the assumed part of a reliability model. Infant mortality, wear-out, confidence bounds, environment, duty cycle, screening, repair, common-cause failures, and population heterogeneity need separate treatment.
- 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
-
Failure rate — Wikipedia contributors
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