similarity-regulator

# Voltage Regulator Similarity Calculator Skill Guidance for working with `VoltageRegulatorSimilarityCalculator` in the lib-electronic-components library. --- **For metadata-driven similarity architecture**, see `/similarity-metadata`: - SpecImportance levels (CRITICAL, HIGH, MEDIUM, LOW, OPTIONAL) - ToleranceRule types (exactMatch, percentageTolerance, minimumRequired, etc.) - SimilarityProfile contexts (DESIGN_PHASE, REPLACEMENT, COST_OPTIMIZATION, etc.) - Calculator integration patterns and gotchas --- ## Overview The `VoltageRegulatorSimilarityCalculator` compares voltage regulators based on: - **Regulator type** - Fixed (78xx/79xx) vs Adjustable (LM317/LM337) - **Output voltage** - Must match for fixed regulators - **Polarity** - Positive vs negative - **Compatible families** - LM317/LM338/LM350 are compatible ## Applicable Types ```java ComponentType.VOLTAGE_REGULATOR // Any type starting with "VOLTAGE_REGULATOR" ``` Returns `false` for `null` type. ## Similarity Thresholds ```java HIGH_SIMILARITY = 0.9; // Same voltage/compatible adjustable MEDIUM_SIMILARITY = 0.7; // Related but different specs LOW_SIMILARITY = 0.3; // Different voltage or polarity ``` ## Fixed Voltage Regulators (78xx/79xx) ### Positive Regulators (78xx) | Part | Output Voltage | |------|----------------| | 7805 | +5V | | 7809 | +9V | | 7812 | +12V | | 7815 | +15V | | 7824 | +24V | ### Negative Regulators (79xx) | Part | Output Voltage | |------|----------------| | 7905 | -5V | | 7912 | -12V | | 7915 | -15V | | 7924 | -24V | ### Fixed Regulator Rules ```java // Same voltage, different manufacturer = HIGH calculator.calculateSimilarity("LM7805", "MC7805", registry); // Returns 0.9 // Different voltage = LOW calculator.calculateSimilarity("LM7805", "LM7812", registry); // Returns 0.3 // Positive vs Negative = LOW calculator.calculateSimilarity("LM7805", "LM7905", registry); // Returns 0.3 ``` ## Adjustable Voltage Regulators ### Positive Adjustable (Compatible Family) | Part | Current | Equivalent | |------|---------|------------| | LM317 | 1.5A | LM317T, LM317K, LM317H | | LM338 | 5A | Compatible with LM317 | | LM350 | 3A | Compatible with LM317 | ### Negative Adjustable | Part | Current | Note | |------|---------|------| | LM337 | 1.5A | Negative equivalent of LM317 | ### Adjustable Regulator Rules ```java // Same adjustable regulator, different package = HIGH calculator.calculateSimilarity("LM317T", "LM317K", registry); // Returns 0.9 // Compatible positive adjustable regulators = HIGH calculator.calculateSimilarity("LM317", "LM350", registry); // Returns 0.9 // Positive vs Negative adjustable = LOW calculator.calculateSimilarity("LM317", "LM337", registry); // Returns 0.3 ``` ## Package Code Handling Common package suffixes: | Code | Package | |------|---------| | T | TO-220 | | CT | TO-220 (different pinout) | | K | TO-3 | | KC | TO-3 | | KV | TO-3 | | H | TO-39 | | S | SOT-223 | | MP | SOT-223 | | DT | TO-252 | ```java // Same regulator, different packages = HIGH calculator.calculateSimilarity("LM7805CT", "LM7805T", registry); // Returns 0.9 ``` ## Manufacturer Prefixes | Prefix | Manufacturer | |--------|--------------| | LM | National/TI | | MC | Motorola/ON Semi | | UA | Fairchild | | L78 | ST | | KA78 | Fairchild | ## Test Examples ```java // Same voltage, different manufacturer calculator.calculateSimilarity("LM7805", "MC7805", registry); // Returns 0.9 // Same adjustable, different package calculator.calculateSimilarity("LM317T", "LM317K", registry); // Returns 0.9 // Compatible adjustable family calculator.calculateSimilarity("LM317", "LM338", registry); // Returns 0.9 // Different voltage calculator.calculateSimilarity("LM7805", "LM7812", registry); // Returns 0.3 // Positive vs negative calculator.calculateSimilarity("LM317", "LM337", registry); // Returns 0.3 // Non-regulator parts calculator.calculateSimilarity("LM358", "LM324", registry); // Returns 0.0 ``` --- ## Learnings & Quirks ### Voltage Detection - The `xx` in 78xx/79xx indicates voltage (05=5V, 12=12V) - Pattern: `7[89](\d{2})` extracts the voltage code ### Adjustable Detection - LM317, LM337, LM338, LM350 are detected by prefix - Package suffixes (T, K, H) come after the number ### Cross-Manufacturer Equivalence - LM7805 ≈ MC7805 ≈ UA7805 ≈ L7805 - All major manufacturers make compatible 78xx parts ### Current Rating - 78Lxx = 100mA (low power) - 78Mxx = 500mA (medium power) - 78xx = 1A (standard) - 78Hxx = 5A (high power) <!-- Add new learnings above this line -->