Littelfuse Manufacturer Skill

Use this skill when working with Littelfuse circuit protection components - TVS diodes, fuses, varistors, and MOVs.

Overview

Littelfuse is a leading manufacturer of circuit protection components. The handler supports:

• TVS Diodes: Transient voltage suppressors for ESD and surge protection
• Fuses: SMD and through-hole fuses for overcurrent protection
• Varistors: Metal oxide varistors (MOVs) for voltage clamping

MPN Structure

TVS Diodes - SM Series (VR-Based Naming)

The SM series uses reverse standoff voltage (VR) in the part number:

SMXJ[Voltage][A/CA]

Component	Description
SM	Surface Mount
X	Package: A=SMA, B=SMB, C=SMC, D=SMD
J	Series designator
Voltage	Reverse standoff voltage (e.g., 5.0, 15, 33)
A	Unidirectional
CA	Bidirectional

Power Ratings by Package:

Series	Package	Power (W)	DO Package
SMAJ	SMA	400	DO-214AC
SMBJ	SMB	600	DO-214AA
SMCJ	SMC	1500	DO-214AB
SMDJ	SMD	3000	-
5.0SMDJ	SMD	5000	-

Examples:

• SMAJ5.0A

  - 400W, 5V standoff, unidirectional, SMA package

• SMBJ33CA

  - 600W, 33V standoff, bidirectional, SMB package

TVS Diodes - P Series (VBR-Based Naming)

The P series uses breakdown voltage (VBR) in the part number:

P[Power][Package][Voltage][A/CA]

Series	Package	Power (W)	Package Type
P4KE	DO-41	400	Axial
P6KE	DO-15	600	Axial
P4SMA	SMA	400	SMD
P6SMB	SMB	600	SMD
1.5KE	DO-15	1500	Axial
1.5SMC	SMC	1500	SMD
3KP	P600	3000	Axial

Examples:

• P6KE6.8A

  - 600W, 6.8V breakdown, unidirectional, axial DO-15

• P6KE15CA

  - 600W, 15V breakdown, bidirectional, axial DO-15

• 1.5KE33CA

  - 1500W, 33V breakdown, bidirectional, axial

Fuses - NANO2 Series

[Series][Current].[Suffix]

Series	Type	Size
0451	Very Fast Acting	6.1 x 2.69mm
0452	Slow Blow (Slo-Blo)	6.1 x 2.69mm
0453	Very Fast Acting	10.1 x 3.12mm
0454	Slow Blow	10.1 x 3.12mm
0448	Nano2 SMF	Square SMD

Suffixes:

• .MRL

  - Mini Reel (1,000 pcs tape & reel)

• .NRL

  - Full Reel (5,000 pcs tape & reel)

Examples:

• 0452005.MRL

  - Slow blow, 5A, mini reel

• 0451002.MRL

  - Very fast acting, 2A, mini reel

• 0448.125

  - Nano2 SMF, 125mA

Varistors - V Series MOVs

Radial Lead MOVs:

V[Voltage][E/P][Size]

Component	Description
V	Varistor prefix
Voltage	Operating voltage (2-3 digits)
E	Epoxy coating
P	Phenolic coating
Size	Disc diameter in mm

Multilayer SMD Varistors (MLE Series):

V[Voltage]MLE[Package][Options]

Examples:

• V07E130P

  - 130V, 7mm disc, epoxy/phenolic

• V18MLE0603N

  - 18V, multilayer, 0603 package

• V26MLE0805N

  - 26V, multilayer, 0805 package

Supported ComponentTypes

• DIODE

  - Base type for all TVS diodes

• TVS_DIODE_LITTELFUSE

  - Specific TVS diode type

• FUSE_LITTELFUSE

  - Fuse type

• VARISTOR_LITTELFUSE

  - Varistor type

Handler Methods

Core Methods

// Pattern matching
boolean matches(String mpn, ComponentType type, PatternRegistry patterns)

// Extraction methods
String extractPackageCode(String mpn)  // Returns package (SMA, SMB, NANO2, etc.)
String extractSeries(String mpn)       // Returns series (SMAJ, P6KE, 0452, etc.)

Littelfuse-Specific Methods

// TVS Diode specific
String extractVoltage(String mpn)      // Returns voltage rating
boolean isBidirectional(String mpn)    // True for CA suffix parts
int getPowerRating(String mpn)         // Returns power in watts

// Fuse specific
String extractCurrentRating(String mpn) // Returns current rating

Usage Examples

LittelfuseHandler handler = new LittelfuseHandler();
PatternRegistry registry = new PatternRegistry();
handler.initializePatterns(registry);

// TVS Diode detection
handler.matches("SMAJ15A", ComponentType.TVS_DIODE_LITTELFUSE, registry); // true
handler.extractPackageCode("SMAJ15A");  // "SMA"
handler.extractVoltage("SMAJ15A");      // "15"
handler.isBidirectional("SMAJ15CA");    // true
handler.getPowerRating("SMAJ15A");      // 400

// Fuse detection
handler.matches("0452005.MRL", ComponentType.FUSE_LITTELFUSE, registry); // true
handler.extractPackageCode("0452005.MRL");  // "NANO2"
handler.extractCurrentRating("0452005.MRL"); // "5"

// Varistor detection
handler.matches("V18MLE0603N", ComponentType.VARISTOR_LITTELFUSE, registry); // true
handler.extractPackageCode("V18MLE0603N");  // "0603"
handler.extractVoltage("V18MLE0603N");      // "18"

Common Selection Guide

TVS Diode Selection by Application

Application	Recommended Series	Power	Package
Low-power signal	SMAJ	400W	SMA
Medium-power	SMBJ	600W	SMB
High-power DC	SMCJ	1500W	SMC
Through-hole	P6KE	600W	DO-15
Low capacitance	SAC	500W	DO-15

Fuse Selection by Characteristics

Characteristic	Recommended Series
Fast acting, SMD	0451
Slow blow, SMD	0452
Fast acting, large	0453
Slow blow, large	0454
Ultra-small SMD	0448

Learnings & Quirks

VR vs VBR Naming Systems

• VR-based (SMAJ, SMBJ, etc.): Part number shows standoff voltage
• VBR-based (P4KE, P6KE, etc.): Part number shows breakdown voltage
• Important: SMAJ10A and P4SMA10A have DIFFERENT voltage characteristics!
  • SMAJ10A has 10V standoff (VR), breakdown is higher
  • P4SMA10A has 10V breakdown (VBR), standoff is lower (~8.5V)

Bidirectional vs Unidirectional

• A

  suffix = Unidirectional (cathode band marking)

• CA

  suffix = Bidirectional (no polarity)
• Gotcha: CA parts have ~2x the capacitance of A parts

Fuse Current Ratings

• Current in 045x series is in the middle:

  0452005

  = 5A
• Leading zeros are significant for sub-1A ratings:

  0452.250

  = 250mA

Package Cross-Reference

Littelfuse	DO Standard	Dimensions
SMA	DO-214AC	4.5 x 2.5 x 2.3mm
SMB	DO-214AA	5.2 x 3.6 x 2.2mm
SMC	DO-214AB	7.1 x 6.2 x 2.3mm

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Related Skills

• /semiconductor

  - General semiconductor handling

• /similarity-diode

  - TVS diode similarity calculations

• /component

  - Base component operations

Test Examples

// Test file: LittelfuseHandlerTest.java
// Location: src/test/java/no/cantara/electronic/component/lib/handlers/

@Test
void shouldDetectSMAJVariants() {
    assertTrue(handler.matches("SMAJ15A", ComponentType.TVS_DIODE_LITTELFUSE, registry));
    assertTrue(handler.matches("SMAJ33CA", ComponentType.TVS_DIODE_LITTELFUSE, registry));
}

@Test
void shouldExtractTVSInfo() {
    assertEquals("SMA", handler.extractPackageCode("SMAJ15A"));
    assertEquals("15", handler.extractVoltage("SMAJ15A"));
    assertEquals(400, handler.getPowerRating("SMAJ15A"));
}