similarity-diode

name: similarity-diode description: Use when working with diode similarity calculations - comparing signal/rectifier/zener/Schottky diode MPNs, understanding equivalent groups like 1N4148/1N914, or diode-specific similarity logic.

Diode Similarity Calculator Skill

Guidance for working with DiodeSimilarityCalculator 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 DiodeSimilarityCalculator compares diodes based on:

• Diode type - Signal, rectifier, zener, Schottky
• Equivalent groups - Known interchangeable parts
• Voltage ratings - For rectifier and zener diodes

Applicable Types

ComponentType.DIODE
// Any type starting with "DIODE_"

Returns false for null type.

Similarity Thresholds

HIGH_SIMILARITY = 0.9;   // Equivalent parts
MEDIUM_SIMILARITY = 0.7; // Same family, compatible
LOW_SIMILARITY = 0.3;    // Same type, different specs

Signal Diode Equivalents

calculator.calculateSimilarity("1N4148", "1N914", registry);
// Returns 0.9 (equivalent signal diodes)

Rectifier Diode Equivalents

1N400x Series (1A Rectifiers)

// Same voltage equivalents
calculator.calculateSimilarity("1N4007", "RL207", registry);
// Returns 0.9 (both 1000V rectifiers)

// Same family, different voltage
calculator.calculateSimilarity("1N4001", "1N4007", registry);
// Returns 0.9 (same family, all rectifiers)

calculator.calculateSimilarity("1N4001", "1N4004", registry);
// Returns >= 0.7 (same family)

Zener Diode Rules

Zener diodes are compared by voltage rating:

// Same voltage zener
calculator.calculateSimilarity("1N4733", "1N4733", registry);
// Returns 0.9

// Different voltage zeners
calculator.calculateSimilarity("1N4733", "1N4742", registry);
// Returns 0.3 (5.1V vs 12V - not interchangeable)

Schottky Diode Equivalents

calculator.calculateSimilarity("BAT54", "BAT54S", registry);
// Returns 0.9 (same Schottky, different configuration)

Test Examples

// Equivalent signal diodes
calculator.calculateSimilarity("1N4148", "1N914", registry);
// Returns 0.9

// Same rectifier diode
calculator.calculateSimilarity("1N4007", "1N4007", registry);
// Returns 0.9

// Cross-manufacturer rectifier
calculator.calculateSimilarity("1N4007", "RL207", registry);
// Returns 0.9

// Same zener voltage
calculator.calculateSimilarity("1N4733", "1N4733", registry);
// Returns 0.9

// Different zener voltage
calculator.calculateSimilarity("1N4733", "1N4742", registry);
// Returns 0.3

// Non-diode parts
calculator.calculateSimilarity("LM358", "LM324", registry);
// Returns 0.0

Learnings & Quirks

1N400x Series Pattern

• 1N = JEDEC prefix
• 400x = 1A rectifier series
• x = voltage code (1=50V through 7=1000V)

Zener Voltage Codes

• 1N47xx series: xx roughly indicates voltage
• Need lookup table for exact voltage

Schottky Configurations

• BAT54 = Single diode
• BAT54S = Series dual (2 diodes in series)
• BAT54A = Common anode
• BAT54C = Common cathode
• These are same diode, different configurations

Signal vs Rectifier

• Signal diodes (1N4148): Fast switching, low current
• Rectifier diodes (1N4007): Higher current, slower