K1300S Equivalent & Substitute Parts Reference

Part Overview

The K1300S is a SIDAC (Silicon Diode for Alternating Current) thyristor manufactured by Littelfuse Inc., rated for 120–138V breakover voltage with 1A peak output current in a DO-214AA/SMB surface mount package. This component is classified as obsolete, making equivalent and substitute parts necessary for ongoing design support and procurement.

SIDACs function as voltage-triggered switches, commonly used in overvoltage protection circuits, surge suppression, and AC line applications. The obsolete status of the K1300S requires identification of active alternatives that maintain electrical and mechanical compatibility.

Substiute Parts

K1300S

Littelfuse Inc.In Stock: 1267K1300S Datasheet

Current PartRFQ

K1300SRP

Littelfuse Inc.In Stock: 3677K1300SRP Datasheet

DirectRFQ

SMP100LC-90

STMicroelectronicsIn Stock: 1946SMP100LC-90 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the K1300S is determined by the following critical parameters:

• Voltage - Breakover: Must fall within or closely match the 120–138V range to ensure proper circuit triggering voltage
• Current - Hold (Ih): Must support the 150 mA maximum hold current requirement
• Package / Case: Must be DO-214AA/SMB to ensure mechanical and thermal compatibility
• Operating Temperature Range: Must support –40°C to 125°C operation
• RoHS Compliance: Must maintain ROHS3 compliance for regulatory alignment

Two substitute parts are identified:

1. K1300SRP (Littelfuse Inc.): Direct equivalent with identical electrical specifications, differentiated only by packaging format (Tape & Reel) and active product status.

2. SMP100LC-90 (STMicroelectronics): TVS thyristor with different electrical characteristics (90V off-state, 125V breakover, 400A peak pulse capability) and different functional application focus, suitable only where the higher current handling and different voltage profile are acceptable.

Parameter Comparison

Engineering Selection Recommendations

K1300SRP is the primary substitute for K1300S. Both parts are manufactured by Littelfuse Inc., share identical electrical specifications (120–138V breakover, 10 µA breakover current, 150 mA hold current, 1A peak output), and are housed in the same DO-214AA/SMB package. The K1300SRP maintains active product status and ROHS3 compliance, making it the direct replacement for obsolete K1300S applications without circuit redesign.

SMP100LC-90 is a secondary option only where circuit requirements permit higher peak pulse current handling (400A vs. 1A) and where the different voltage profile (90V off-state, 125V breakover) aligns with application needs. This part represents a functional alternative rather than a direct equivalent, as it is categorized as a TVS thyristor rather than a SIDAC and introduces different electrical behavior. Selection of SMP100LC-90 requires circuit validation.

Both substitute parts maintain ROHS3 compliance and are available in active inventory status, ensuring long-term supply continuity.

Frequently Asked Questions (FAQ)

Q: Can K1300SRP be used as a direct replacement for K1300S?

A: Yes. K1300SRP is electrically and mechanically identical to K1300S. Both share the same breakover voltage range (120–138V), hold current (150 mA), peak output current (1A), operating temperature range (–40°C to 125°C), and DO-214AA/SMB package. The only difference is packaging format (Tape & Reel for K1300SRP) and active product status. No circuit modifications are required.

Q: What is the difference between K1300S/K1300SRP and SMP100LC-90?

A: K1300S and K1300SRP are SIDACs with 120–138V breakover voltage and 1A peak output current. SMP100LC-90 is a TVS thyristor with 125V breakover voltage and 400A peak pulse current (8/20µs). While both fit the DO-214AA/SMB package, SMP100LC-90 has significantly higher current handling capability and different voltage characteristics. Selection depends on whether the application requires the higher current capacity and can tolerate the different electrical profile.

Q: Are all three parts RoHS compliant?

A: Yes. K1300S, K1300SRP, and SMP100LC-90 are all ROHS3 compliant, meeting regulatory requirements for lead-free and restricted substance compliance.

Q: What is the packaging difference between K1300S and K1300SRP?

A: K1300S is supplied in standard packaging format. K1300SRP is supplied in Tape & Reel (TR) format, which is standard for automated assembly processes. Both use the same DO-214AA/SMB case. The packaging format does not affect electrical performance or mechanical fit.

Q: Is SMP100LC-90 a suitable substitute for all K1300S applications?

A: SMP100LC-90 is suitable only where the application can accommodate higher peak pulse current (400A) and where the different voltage characteristics (90V off-state, 125V breakover) are compatible with circuit design. For standard SIDAC applications requiring 1A peak output and 120–138V triggering, K1300SRP is the recommended substitute. Circuit validation is required before selecting SMP100LC-90.