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Radiation Test Playbook: TID / SEE with Simple Orbit Calculators

· One min read
Sampras Zheng
Sampras Zheng
Engineer

This page updates my radiation test blog into a practical engineering workflow and includes simple simulation tools.

These two calculators are for quick mission trade studies, not qualification signoff.

Simple Orbital TID Calculator

Trend-only tool: dose or shielding versus orbit across LEO/MEO/GEO/Lunar.

Orbit:

Mission duration (years):

Al equivalent shielding (mm):

LEO altitude (km):

LEO inclination (deg):

Device TID limit (krad(Si)):

Estimated mission TID: 2.17 krad(Si)

Estimated shielding to meet TID limit: 2 mm Al eq.

Simple Orbital SEE Calculator

Trend-only tool: expected SEE events across LEO/MEO/GEO/Lunar.

Orbit:

Mission duration (days):

Al equivalent shielding (mm):

LET threshold (MeV*cm2/mg):

Device cross-section sigma (cm2/event):

Sensitive/protected bits:

Estimated SEE/day: 8.521e-7

Expected SEE in mission: 0.0003

Probability of at least one SEE: 0.03%

Practical Flow (Aligned with TI-style Radiation Qualification)​

  1. Define mission profile first: orbit, lifetime, shielding stack-up, reliability target.
  2. Screen TID margin with system-level assumptions.
  3. Characterize SEE sensitivity (SEU/SEL/SEFI/SET) using LET threshold and cross-section from test data.
  4. Build mitigation at design level:
    • ECC/scrubbing for memory
    • watchdog/recovery paths for functional interrupts
    • current limiting and latch-up protection for SEL risk
  5. Re-run mission-level estimates with mitigation assumptions, then lock test plan.

Notes on Model Limits​

  • TID model here is an exponential shielding trend approximation.
  • SEE model here is a Poisson-style expectation model using orbit-dependent baseline.
  • For production decisions, use full environment tools and part-level radiation reports.

References​