HT60RP Equivalent & Substitute Parts

Part Overview

The HT60RP is a Diac/Sidac thyristor manufactured by Littelfuse Inc., rated for 56–70V breakover voltage with 1.5A peak output current in a DO-35 axial package. This component is classified as obsolete, making equivalent substitutes necessary for ongoing production and maintenance applications. Substitute parts must maintain electrical compatibility within the allowed parameter ranges for this thyristor category while meeting packaging and compliance requirements.

Substiute Parts

HT60RP

Littelfuse Inc.In Stock: 1087HT60RP Datasheet

Current PartRFQ

DB3

Fairchild SemiconductorIn Stock: 770983DB3 Datasheet

MFR RecommendedRFQ

DB3TG

STMicroelectronicsIn Stock: 2484DB3TG Datasheet

MFR RecommendedRFQ

DB4

STMicroelectronicsIn Stock: 20892DB4 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the HT60RP is determined by the following electrical and mechanical criteria:

• Package Compatibility: All substitute parts must use DO-204AH / DO-35 axial packaging to ensure mechanical fit and lead configuration compatibility.
• Breakover Voltage Range: Substitute parts operate within defined voltage windows. The HT60RP operates at 56–70V; substitutes are grouped by their respective breakover voltage ranges.
• Current Ratings: Peak output current must meet or exceed the application requirement. The HT60RP is rated for 1.5A; available substitutes provide 2A capability.
• Breakover Current: Specified at 15 µA or 50 µA depending on the part.
• Temperature Range: All parts maintain –40°C to 125°C operating range.
• Compliance: All parts are ROHS3 compliant and carry EAR99 ECCN classification.

Substitutes are available in three voltage bands: 28–36V (DB3), 30–34V (DB3TG), and 35–45V (DB4). Selection depends on the specific breakover voltage requirement of the application.

Parameter Comparison

Engineering Selection Recommendations

DB3 (Fairchild Semiconductor): Operates at 28–36V breakover voltage. This part is obsolete and carries 50 µA breakover current. Selection is appropriate only when the application circuit is designed for the lower voltage band and obsolescence risk is acceptable.

DB3TG (STMicroelectronics): Operates at 30–34V breakover voltage with 15 µA breakover current matching the HT60RP specification. This part carries active product status, ensuring ongoing availability and supply chain stability. REACH Unaffected designation confirms regulatory compliance. This is the preferred substitute when voltage requirements align with the 30–34V range.

DB4 (STMicroelectronics): Operates at 35–45V breakover voltage with 50 µA breakover current. This part carries active product status and REACH Unaffected designation. Selection is appropriate for applications requiring the 35–45V voltage band with higher breakover current tolerance.

All substitute parts exceed the HT60RP peak output current specification (1.5A vs. 2A available), providing margin for application requirements.

Frequently Asked Questions (FAQ)

Q: Can DB3, DB3TG, or DB4 be used as direct replacements for HT60RP?

A: Direct replacement depends on the application's breakover voltage requirement. The HT60RP operates at 56–70V. None of the listed substitutes operate in this voltage range. These parts are suitable only if the circuit design can accommodate lower voltage operation (28–45V range). Verify the application schematic to confirm voltage compatibility before substitution.

Q: What is the difference between DB3 and DB3TG?

A: Both operate in overlapping voltage ranges (DB3: 28–36V; DB3TG: 30–34V). DB3TG is manufactured by STMicroelectronics with active product status, while DB3 (Fairchild) is obsolete. DB3TG matches the HT60RP breakover current specification at 15 µA, whereas DB3 specifies 50 µA. For new designs, DB3TG is preferred due to active status and current specification alignment.

Q: Are all substitute parts in the same package?

A: Yes. All parts—HT60RP, DB3, DB3TG, and DB4—use DO-204AH / DO-35 axial packaging, ensuring mechanical and lead compatibility.

Q: What is the impact of different breakover current specifications?

A: Breakover current (15 µA vs. 50 µA) affects the gate trigger sensitivity. The HT60RP and DB3TG both specify 15 µA, while DB3 and DB4 specify 50 µA. Higher breakover current requires greater gate drive to trigger the device. Circuit design must account for this difference to ensure reliable operation.

Q: Are all parts RoHS compliant?

A: Yes. All parts carry ROHS3 compliance certification and are suitable for applications requiring RoHS-compliant components.

Q: What is the significance of product status (Active vs. Obsolete)?

A: Active parts (DB3TG, DB4) have ongoing manufacturer support and supply availability. Obsolete parts (HT60RP, DB3) have limited or no future availability. For new production, active parts are preferred to ensure long-term supply chain stability.