DB4-TP Equivalent & Substitute Parts

Part Overview

The DB4-TP is a bidirectional thyristor (DIAC) manufactured by Micro Commercial Co, designed for applications requiring breakover voltage in the 35–45V range. This component is classified as obsolete, necessitating identification of equivalent alternatives from active manufacturers to ensure supply chain continuity and design reliability.

Substiute Parts

DB4-TP

Micro Commercial CoIn Stock: 1068DB4-TP Datasheet

Current PartRFQ

DB3TG

STMicroelectronicsIn Stock: 2484DB3TG Datasheet

SimilarRFQ

DB4

STMicroelectronicsIn Stock: 20892DB4 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the DB4-TP is determined by the following critical parameters:

• Voltage - Breakover Range: Must match 35–45V to ensure correct circuit triggering behavior
• Current - Peak Output: Must equal or exceed 2 A for adequate load handling
• Package / Case: Must be DO-35 or equivalent axial package for mechanical and thermal compatibility
• Operating Temperature Range: Must support –40°C to 125°C minimum
• RoHS Compliance: Must meet ROHS3 standard for regulatory alignment

Based on these criteria, the following parts qualify as direct substitutes:

1. DB4 (STMicroelectronics) – Exact voltage and current match, active product status
2. DB3TG (STMicroelectronics) – Lower voltage range (30–34V), suitable only for applications with reduced voltage requirements

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: DB4 (STMicroelectronics)

The DB4 from STMicroelectronics is the direct equivalent to DB4-TP. It maintains identical voltage and current specifications, operates across the same temperature range, and is available in active production status with 20,830 units in stock. Both parts are ROHS3 compliant and carry MSL rating 1. This part is suitable for direct replacement in all applications originally designed for DB4-TP.

Secondary Substitute: DB3TG (STMicroelectronics)

The DB3TG is a lower-voltage alternative with a breakover range of 30–34V. This part is applicable only to circuits designed to operate at reduced trigger voltages. It shares identical package geometry, temperature range, and compliance certifications. Selection of DB3TG requires circuit-level verification that the lower breakover voltage is compatible with the intended application.

Frequently Asked Questions (FAQ)

Q: Can DB4 directly replace DB4-TP without circuit modification?

A: Yes. The DB4 from STMicroelectronics matches the voltage breakover range (35–45V), peak current rating (2 A), operating temperature range (–40°C to 125°C), and package specification (DO-35 axial). No circuit modification is required.

Q: What is the difference between DB4-TP and DB4?

A: Both parts share identical electrical specifications for voltage and current. The primary difference is manufacturer (Micro Commercial Co versus STMicroelectronics) and product status (obsolete versus active). The DB4 is currently in production with higher inventory availability.

Q: When should DB3TG be used instead of DB4?

A: DB3TG is appropriate only when the circuit is designed to trigger at a lower voltage threshold (30–34V range). If the original design requires 35–45V breakover, DB3TG will trigger prematurely and is not suitable.

Q: Are all substitute parts available in the same package?

A: Yes. DB4, DB4-TP, and DB3TG are all specified in DO-35 axial package (DO-204AH). Mechanical and thermal compatibility is maintained across all three parts.

Q: Do the substitute parts meet the same compliance standards?

A: Yes. DB4 and DB3TG are both ROHS3 compliant with MSL rating 1 (unlimited moisture sensitivity level), matching the compliance profile of DB4-TP.