Electronic Component Skill

This skill provides guidance for working with electronic components in the lib-electronic-components library.

Core Concepts

Component Type Hierarchy

Components are classified using ComponentType enum with two levels:

• Base types: RESISTOR, CAPACITOR, MOSFET, OPAMP, etc.
• Manufacturer-specific types: MOSFET_INFINEON, CAPACITOR_CERAMIC_MURATA, etc.

Use getBaseType() to map specific types to their base type.

Key Classes

Class	Purpose
ComponentType	Enum of ~200 component types with passive/semiconductor flags
ComponentManufacturer	Enum of manufacturers with regex patterns
ManufacturerHandler	Interface for manufacturer-specific MPN parsing
MPNUtils	Static utilities for MPN normalization, similarity, type detection
BOMEntry	Component entry in a bill of materials

Adding a New Manufacturer Handler

1. Create handler in src/main/java/no/cantara/electronic/component/lib/manufacturers/:

public class NewMfrHandler implements ManufacturerHandler {
    @Override
    public void initializePatterns(PatternRegistry registry) {
        registry.registerPattern(ComponentType.RESISTOR,
            Pattern.compile("^NMF[0-9]{4}.*", Pattern.CASE_INSENSITIVE));
    }

    @Override
    public String extractPackageCode(String mpn) { /* ... */ }

    @Override
    public String extractSeries(String mpn) { /* ... */ }

    @Override
    public boolean isOfficialReplacement(String mpn1, String mpn2) { return false; }

    @Override
    public Set<ManufacturerComponentType> getManufacturerTypes() { return Set.of(); }

    @Override
    public Set<ComponentType> getSupportedTypes() {
        return Set.of(ComponentType.RESISTOR);
    }
}

2. Add entry to ComponentManufacturer enum:

NEW_MFR("(?:NMF)[0-9]", "New Manufacturer", new NewMfrHandler()),

Adding a New Component Type

1. Add to ComponentType enum with passive/semiconductor flags:

NEW_TYPE(false, true),  // (isPassive, isSemiconductor)
NEW_TYPE_MANUFACTURER(false, true),

2. Update getBaseType() switch to map specific types to base:

case NEW_TYPE_INFINEON, NEW_TYPE_ST -> NEW_TYPE;

3. Add patterns in relevant manufacturer handlers

MPN Operations

// Normalize MPN (removes special characters)
String normalized = MPNUtils.normalize("LM358-N"); // "LM358N"

// Strip package suffix to get base part number
String base = MPNUtils.stripPackageSuffix("MAX3483EESA+"); // "MAX3483EESA"
String base2 = MPNUtils.stripPackageSuffix("LTC2053HMS8#PBF"); // "LTC2053HMS8"

// Generate search variations (for datasheet/component searches)
List<String> vars = MPNUtils.getSearchVariations("TJA1050T/CM,118");
// ["TJA1050T/CM,118", "TJA1050T"]

// Check component equivalence (ignoring package suffixes)
boolean equiv = MPNUtils.isEquivalentMPN("LTC2053HMS8#PBF", "LTC2053HMS8#TR"); // true

// Extract package suffix
Optional<String> suffix = MPNUtils.getPackageSuffix("MAX3483EESA+"); // Optional.of("+")

// Detect manufacturer
ComponentManufacturer mfr = ComponentManufacturer.fromMPN("STM32F103C8T6");

// Detect component type
ComponentType type = ComponentType.fromMPN("IRF540N"); // MOSFET

// Calculate similarity
double sim = MPNUtils.calculateSimilarity("LM358", "MC1458"); // 0.9

Package Suffix Support

MPNUtils now supports manufacturer-specific package suffixes:

• Maxim/AD: + (lead-free) - e.g., MAX3483EESA+
• Linear Tech: #PBF, #TR (RoHS, Tape & Reel) - e.g., LTC2053HMS8#PBF
• NXP: /CM,118 (ordering codes) - e.g., TJA1050T/CM,118
• Various: ,315 (ordering codes) - e.g., NC7WZ04,315

Use cases:

• Datasheet searches: Try both original and base MPN
• Component deduplication: Same base = same component
• BOM validation: Match supplier MPNs to design MPNs
• Inventory matching: Ignore packaging differences

Similarity Calculators

Each component type can have a dedicated similarity calculator in componentsimilaritycalculators/:

• ResistorSimilarityCalculator - compares resistance values, tolerances, packages
• CapacitorSimilarityCalculator - compares capacitance, voltage, dielectric
• MosfetSimilarityCalculator - compares Vds, Rds(on), package
• etc.

Implement ComponentSimilarityCalculator interface and add to list in MPNUtils.

Testing

Run component-related tests:

mvn test -Dtest=MPNUtilsTest
mvn test -Dtest=ComponentTypeDetectorTest
mvn test -Dtest=MPNExtractionTest

Related Skills

Use specialized skills for specific component types:

• /resistor - Resistor patterns and value extraction
• /capacitor - Capacitor patterns and specifications
• /semiconductor - Diodes, transistors, MOSFETs
• /ic - Microcontrollers, op-amps, voltage regulators
• /connector - Connector manufacturer patterns
• /memory - Flash, EEPROM, RAM components

See Also

Advanced Skills

• /handler-pattern-design - Handler patterns, anti-patterns, and testing strategies
• /mpn-normalization - MPN suffix handling and normalization patterns
• /component-type-detection-hierarchy - Type hierarchy, specificity levels, getBaseType() mapping
• /component-spec-extraction - Spec extraction patterns and naming conventions
• /manufacturer-detection-from-mpn - Manufacturer regex patterns and detection ordering

Documentation

• HISTORY.md - Handler bug patterns and fixes (PR #89, handler cleanup PRs #73-88)
• .docs/history/HANDLER_IMPLEMENTATION_PATTERNS.md - Detailed handler development patterns
• .docs/history/BUG_FIX_ANALYSIS.md - Critical bugs and prevention strategies

Recording Learnings

Important: When you discover quirks, edge cases, or important patterns while working on components:

1. General/cross-cutting learnings → Add to CLAUDE.md under "Learnings & Quirks"
2. Component-specific learnings → Add to the relevant skill file below

Examples of what to record:

• MPN patterns that don't follow expected conventions
• Manufacturer-specific quirks in part numbering
• Edge cases in similarity calculation
• Test failures that revealed unexpected behavior
• Regex patterns that needed adjustment

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Learnings & Quirks

Handler Patterns

• Use registry.addPattern() not registry.registerPattern() - the latter requires a compiled Pattern object
• Handler order in ComponentManufacturer enum affects detection priority for ambiguous MPNs

MPN Edge Cases

• Some MPNs contain hyphens that are significant (e.g., Molex 43045-0212) vs decorative (e.g., LM358-N)
• Yageo resistors: RC0603FR-0710KL - the -07 is TCR code, not a separator

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