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name: similarity-regulator description: Use when working with voltage regulator similarity calculations - comparing 78xx/79xx fixed regulators, LM317/LM337 adjustable regulators, or voltage regulator-specific similarity logic.

Voltage Regulator Similarity Calculator Skill

Guidance for working with VoltageRegulatorSimilarityCalculator in the lib-electronic-components library.

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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

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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

CopyComponentType.VOLTAGE_REGULATOR
// Any type starting with "VOLTAGE_REGULATOR"

Returns false for null type.

Similarity Thresholds

CopyHIGH_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)

Negative Regulators (79xx)

Fixed Regulator Rules

Copy// 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)

Negative Adjustable

Adjustable Regulator Rules

Copy// 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:

Copy// Same regulator, different packages = HIGH
calculator.calculateSimilarity("LM7805CT", "LM7805T", registry);
// Returns 0.9

Manufacturer Prefixes

Test Examples

Copy// 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

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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)