DB4-AP Equivalent & Substitute Parts

Part Overview

The DB4-AP 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, making equivalent substitutes necessary for ongoing production and maintenance applications. The DB4-AP operates across the industrial temperature range of -40°C to 125°C and is packaged in the DO-35 axial format, a standard configuration for discrete thyristor devices.

Substiute Parts

DB4-AP

Micro Commercial CoIn Stock: 901DB4-AP Datasheet

Current PartRFQ

DB3TG

STMicroelectronicsIn Stock: 2484DB3TG Datasheet

SimilarRFQ

DB4

STMicroelectronicsIn Stock: 20892DB4 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

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

• Voltage - Breakover Range: 35–45V (primary selection criterion)
• Current - Peak Output: 2 A (maximum current handling capability)
• Package / Case: DO-35 axial format (mechanical and thermal compatibility)
• Operating Temperature Range: -40°C to 125°C (environmental suitability)
• RoHS Compliance: ROHS3 Compliant (regulatory requirement)

Two substitute parts meet these criteria and are available as active products from established manufacturers. Both maintain the identical breakover voltage range, peak current rating, package format, and temperature operating range as the DB4-AP.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: DB4 (STMicroelectronics)

The DB4 from STMicroelectronics is the direct equivalent to the DB4-AP. It maintains identical breakover voltage (35–45V), peak current (2 A), package format (DO-35), and operating temperature range (-40°C to 125°C). The DB4 is an active product with ROHS3 compliance and unlimited moisture sensitivity rating. This part provides the closest functional match with the advantage of current manufacturing availability (20,830 pcs in stock).

Secondary Substitute: DB3TG (STMicroelectronics)

The DB3TG is suitable only for applications where a lower breakover voltage (30–34V) is acceptable. While it shares the same peak current rating, package format, and temperature range, the reduced breakover voltage makes it applicable only to circuits designed for the 30–34V threshold. The DB3TG is an active product with ROHS3 compliance and is available in quantity (2,420 pcs in stock).

Frequently Asked Questions (FAQ)

Q: Can the DB4 (STMicroelectronics) directly replace the DB4-AP?

A: Yes. The DB4 from STMicroelectronics is a direct functional equivalent. Both parts share the same breakover voltage range (35–45V), peak current rating (2 A), DO-35 package format, and operating temperature range (-40°C to 125°C). The DB4 is an active product, whereas the DB4-AP is obsolete.

Q: What is the difference between the DB4 and DB3TG substitutes?

A: The primary difference is breakover voltage. The DB4 operates at 35–45V, matching the DB4-AP specification. The DB3TG operates at a lower breakover voltage of 30–34V. Both share identical peak current (2 A), package format (DO-35), and temperature range. Select DB3TG only if your circuit is designed for the lower voltage threshold.

Q: Are both substitutes RoHS compliant?

A: Yes. Both the DB4 and DB3TG from STMicroelectronics are ROHS3 compliant, matching the compliance status of the DB4-AP.

Q: Does the DO-35 package format remain the same across all three parts?

A: Yes. The DB4-AP, DB4, and DB3TG all use the DO-35 axial package format (DO-204AH designation), ensuring mechanical and thermal compatibility in existing circuit designs.

Q: What is the operating temperature range for these substitutes?

A: All three parts operate across the same temperature range: -40°C to 125°C (junction temperature). This ensures thermal compatibility in applications requiring industrial temperature performance.

Q: Why is the DB4-AP listed as obsolete?

A: The DB4-AP from Micro Commercial Co has reached end-of-life status. The DB4 from STMicroelectronics provides an active, currently manufactured equivalent with identical electrical and mechanical specifications.