Derating Analysis for Electronic Components

Qu'est-ce que l'analyse de déclassement des composants?

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.

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.

Figure 2: Exemple de directive de déclassement des composants

 

L'analyse détecte les composants de surévaluation (rouge) et de sur-déclassement (jaune). Les composants surdimensionnés sont également détectés lorsque la contrainte est bien inférieure à la cote.
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.

Features:

• 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.
• Les directives de déclassement peuvent être personnalisées selon les normes [1-6] ou les pratiques de votre entreprise.
• Thermal placement guidelines in the form of a Pareto list, for optimal placement during layout.

Utilisations supplémentaires pour les résultats de 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.

 

 

Références:

[1] ECSS-Q-ST-30-11C Assurance produit spatial - Déclassement - Composants EEE
[2] Directive de déclassement de l'US Navy, SD-18
[3] Commande spatiale de l'armée de l'air SMC Standard SMC-S-010
[4] Instructions NASA EEE-INST-002 pour la sélection, le dépistage, la qualification et le déclassement des pièces EEE
[5] Paramètres de performance IPC-9592 pour les dispositifs de conversion de puissance
[6] Mil-Hdbk-338 Military Handbook Electronic Reliability Design Handbook