Equivalent & Substitute Parts for 12TQ040 Schottky Diode

Part Overview

The 12TQ040 is a Schottky rectifier diode rated for 40 V DC reverse voltage and 15 A average rectified current in a TO-220AC package. Manufactured by Vishay General Semiconductor - Diodes Division, this component is classified as obsolete. Due to its obsolete status and limited availability from the original manufacturer, equivalent and substitute parts from active manufacturers are necessary for new designs and ongoing production requirements. Substitute parts maintain electrical compatibility while offering improved availability and compliance with current regulatory standards.

Substiute Parts

12TQ040

Vishay General Semiconductor - Diodes DivisionIn Stock: 76212TQ040 Datasheet

Current PartRFQ

MBR1645G

onsemiIn Stock: 17047MBR1645G Datasheet

MFR RecommendedRFQ

STPS1545D

STMicroelectronicsIn Stock: 35289STPS1545D Datasheet

MFR RecommendedRFQ

12TQ040

SMC Diode SolutionsIn Stock: 91912TQ040 Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the 12TQ040 is determined by the following electrical and mechanical parameters:

Primary Substitution Criteria:

• Voltage - DC Reverse (Vr) rating equal to or greater than 40 V
• Current - Average Rectified (Io) rating equal to or greater than 15 A
• Schottky diode technology with fast recovery characteristics (≤ 500ns, > 200mA)
• Through-hole mounting configuration
• TO-220-2 or TO-220AC package compatibility

Substitute Classification:

MFR Recommended Substitutes exceed the original specifications while maintaining full electrical compatibility. These parts are from active manufacturers with current product status and improved regulatory compliance.

Parametric Equivalent maintains identical electrical specifications and package configuration, offering direct replacement capability with enhanced availability and compliance status.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement with Identical Specifications:

The 12TQ040 from SMC Diode Solutions is a parametric equivalent offering identical electrical ratings (40 V, 15 A, 560 mV forward voltage) and package configuration. This part is currently active with ROHS3 compliance, providing a direct substitution path for existing designs without circuit modification.

For Enhanced Performance and Availability:

The MBR1645G from onsemi provides increased voltage rating (45 V) and current capacity (16 A) while maintaining fast recovery characteristics. This part is from an active manufacturer with ROHS3 compliance and significantly higher inventory availability. The MBR1645G is suitable for applications where the additional voltage and current margin provides design flexibility.

The STPS1545D from STMicroelectronics maintains the original 15 A current rating with elevated voltage rating (45 V). This part is active with ROHS3 compliance and extensive inventory availability. The STPS1545D is appropriate for designs requiring the original current specification with improved voltage headroom.

Compliance Considerations:

All substitute parts from active manufacturers (onsemi, STMicroelectronics, SMC Diode Solutions) are ROHS3 compliant, addressing regulatory requirements that the original Vishay part does not meet. Selection should prioritize active manufacturer parts to ensure long-term supply chain stability and compliance with current environmental standards.

Frequently Asked Questions (FAQ)

Q: Can the MBR1645G replace the 12TQ040 in all applications?

A: The MBR1645G has higher voltage (45 V vs. 40 V) and current (16 A vs. 15 A) ratings, making it electrically compatible for applications designed for the 12TQ040. The higher ratings provide additional design margin. However, the forward voltage specification is measured at a different current level (630 mV @ 16 A vs. 560 mV @ 15 A), which may affect thermal performance in specific circuit designs.

Q: What is the difference between the two 12TQ040 parts listed?

A: Both are 12TQ040 Schottky diodes with identical electrical specifications (40 V, 15 A, 560 mV forward voltage). The Vishay part is obsolete, while the SMC Diode Solutions part is active with ROHS3 compliance and improved availability. The SMC part is the recommended direct replacement.

Q: Are all substitute parts in the same package?

A: All parts use the TO-220-2 package with through-hole mounting. The Vishay and SMC parts use TO-220AC designation, while onsemi and STMicroelectronics use TO-220-2 designation. These designations refer to the same physical package and are mechanically and electrically interchangeable.

Q: Why do the forward voltage specifications differ across parts?

A: Forward voltage is measured at specific current levels. The 12TQ040 is specified at 15 A, the MBR1645G at 16 A, and the STPS1545D at 30 A. These measurements reflect the diode characteristics at different operating points. For direct comparison at the same current level, consult detailed datasheets.

Q: Which substitute part has the best availability?

A: The STPS1545D from STMicroelectronics has the highest inventory (35,200 pcs), followed by the MBR1645G from onsemi (17,020 pcs). Both are significantly higher than the original Vishay part (699 pcs).

Q: Are all substitute parts RoHS compliant?

A: Yes. All substitute parts from onsemi (MBR1645G), STMicroelectronics (STPS1545D), and SMC Diode Solutions (12TQ040) are ROHS3 compliant. The original Vishay 12TQ040 is RoHS non-compliant.

Q: Can I use the STPS1545D if my circuit requires exactly 15 A?

A: Yes. The STPS1545D is rated for 15 A average rectified current, matching the original specification. The higher voltage rating (45 V vs. 40 V) does not affect current capacity and provides additional voltage margin for the application.