Derating Analysis for Electronic Components

Che cos'è l'analisi del declassamento dei componenti?

The maximum rating for applied component stress (current, voltage, power, temperature, etc.) is defined by the manufacturer, and even stricter derating guidelines are defined to increase product robustness. Component derating analysis defines the optimal operating range for each component.


Why You Need Component Derating Analysis

Component damage may occur when it is subjected to power, current, voltage, or temperature which surpass its maximum stress rating.
Electrical overstress affects product performance, and is the leading cause of field returns.

Failure Pareto Analysis

Figure 1: Typical failure Pareto analysis


Many engineers select components that have a maximal rating which is twice the expected actual stress. However, as temperatures increase, component performance deteriorates, this practice becomes insufficient, and derating guidelines must be applied.


Component derating analysis helps you select the optimal components rating according to stress load and temperature.

Derating analysis for electronic components

Figura 2: esempio di linee guida per il declassamento dei componenti


L'analisi rileva i componenti di over-rating (rosso) e over-derating (giallo). I componenti sovra-progettati vengono rilevati anche quando lo stress è molto inferiore al valore nominale.
In many companies, the process is performed manually and includes time-consuming tasks: Calculating component stresses and comparing the result with the derating guidelines for each component type.


BQR Component Derating Analysis

The BQR solution automates the manual process of component stress and derating analysis, optimizing the component selection for reliability and cost effectiveness.


  • Plug-Ins for major E-CADs (Altium, Mentor, OrCad) provide easy BOM import as well as presenting results on the schematic design.
  • Stress can be input semi-automatically, or calculated using a unique circuit stress simulator.
  • Le linee guida per il declassamento possono essere personalizzate in base agli standard [1-6] o alla prassi della propria azienda.
  • Thermal placement guidelines in the form of a Pareto list, for optimal placement during layout.

Ulteriori usi per i risultati dello stress:

Once the component stresses are defined, additional analyses can be held:

  • BQR’s patented schematic review detects a wide variety of design errors before layout. Some of the errors depend on stress, for example: incorrect applied voltage.
  • BQR’s MTBF calculation software uses the defined stresses for realistic MTBF prediction.




[1] ECSS-Q-ST-30-11C Garanzia del prodotto spaziale - Declassamento - Componenti EEE
[2] Linee guida sul declassamento della Marina degli Stati Uniti, SD-18
[3] Comando spaziale dell'aeronautica militare SMC Standard SMC-S-010
[4] Istruzioni NASA EEE-INST-002 per la selezione, lo screening, la qualificazione e il declassamento delle parti EEE
[5] IPC-9592 Parametri di prestazione per dispositivi di conversione di potenza
[6] Manuale militare Mil-Hdbk-338 Manuale di progettazione elettronica dell'affidabilità