MBRB745 Equivalent & Substitute Parts

Part Overview

The MBRB745 is a Schottky rectifier diode rated for 45 V DC reverse voltage and 7.5 A average rectified current in a surface mount D2PAK (TO-263AB) package. The original Vishay General Semiconductor version is classified as obsolete, necessitating identification of equivalent and upgraded alternatives from active manufacturers. Substitute parts must maintain electrical performance within the specified voltage, current, and thermal operating ranges while supporting modern manufacturing and compliance requirements.

Substiute Parts

MBRB745

Vishay General Semiconductor - Diodes DivisionIn Stock: 3869MBRB745 Datasheet

Current PartRFQ

MBRB745

SMC Diode SolutionsIn Stock: 3850MBRB745 Datasheet

DirectRFQ

STPS745G-TR

STMicroelectronicsIn Stock: 16137STPS745G-TR Datasheet

UpgradeRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MBRB745 is determined by strict equivalence across the following electrical and mechanical parameters:

Critical Matching Parameters:

• Voltage - DC Reverse (Vr) (Max): 45 V
• Current - Average Rectified (Io): 7.5 A
• Technology: Schottky
• Package / Case: TO-263-3, D2PAK (TO-263AB)
• Mounting Type: Surface Mount
• Speed: Fast Recovery ≤ 500 ns, > 200 mA (Io)
• Current - Reverse Leakage @ Vr: 100 µA @ 45 V

Acceptable Variation Parameters:

• Voltage - Forward (Vf) (Max) @ If: Specified at different current levels (7.5 A or 15 A) with same maximum value of 840 mV
• Operating Temperature - Junction: Extended upper temperature limits are acceptable
• Capacitance @ Vr, F: Not specified for all parts; absence does not disqualify substitution
• Product Status: Active products are preferred over obsolete; however, direct equivalents from active manufacturers are prioritized
• RoHS and REACH Compliance: Modern compliance certifications are preferred but do not affect electrical substitutability

Parameter Comparison

Engineering Selection Recommendations

Direct Equivalent (MBRB745 by SMC Diode Solutions): The MBRB745 from SMC Diode Solutions is a direct electrical and mechanical equivalent to the obsolete Vishay part. It maintains identical voltage, current, and package specifications. This part is currently in active production status with ROHS3 compliance and Tape & Reel packaging, making it suitable for immediate replacement in existing designs without circuit modification.

Upgraded Alternative (STPS745G-TR by STMicroelectronics): The STPS745G-TR is an upgraded substitute that meets all critical electrical parameters while offering extended maximum junction temperature capability (175°C vs. 150°C). This part is actively produced by STMicroelectronics with ROHS3 compliance and Tape & Reel packaging. The higher temperature rating provides additional thermal margin in applications operating near the upper temperature limit of the original design.

Both substitute parts are suitable for direct replacement based on electrical equivalence and package compatibility. Selection between the direct equivalent and upgraded alternative depends on design requirements for thermal headroom and supply chain availability.

Frequently Asked Questions (FAQ)

Q: Can the MBRB745 (SMC Diode Solutions) be used as a direct replacement for the obsolete Vishay MBRB745?

A: Yes. The SMC Diode Solutions MBRB745 is electrically and mechanically equivalent. It maintains the same 45 V reverse voltage rating, 7.5 A average rectified current, fast recovery Schottky technology, and D2PAK package configuration. No circuit modifications are required.

Q: What is the difference between the MBRB745 (SMC) and STPS745G-TR (STMicroelectronics)?

A: Both parts are electrically equivalent at the specified operating parameters. The primary difference is the maximum junction temperature: MBRB745 (SMC) is rated to 150°C, while STPS745G-TR is rated to 175°C. The STPS745G-TR provides 25°C additional thermal margin. Both are ROHS3 compliant and available in Tape & Reel packaging.

Q: Are there any package compatibility issues when substituting these parts?

A: No. All three parts use the identical TO-263-3 D2PAK (TO-263AB) surface mount package with 2 leads plus tab. PCB footprints and assembly processes remain unchanged.

Q: Does the forward voltage specification difference affect substitutability?

A: No. The original Vishay part specifies 840 mV @ 7.5 A, while the substitute parts specify 840 mV @ 15 A. Both meet the maximum forward voltage requirement of 840 mV. The substitute specifications are measured at higher current, confirming performance at the design operating point.

Q: What is the significance of the capacitance specification in the SMC part?

A: The SMC MBRB745 provides a capacitance specification (400 pF @ 5 V, 1 MHz) that is not listed for the original Vishay or STMicroelectronics parts. This additional data does not affect substitutability; it provides supplementary information for high-frequency circuit analysis if required.

Q: Are RoHS and REACH compliance requirements met by the substitute parts?

A: Yes. Both the MBRB745 (SMC Diode Solutions) and STPS745G-TR (STMicroelectronics) are ROHS3 compliant. The STPS745G-TR is REACH Unaffected, while the SMC part is REACH Affected. Compliance status should be verified against specific application and regional requirements.

Q: What is the minimum operating temperature range for these parts?

A: The original Vishay MBRB745 operates from -65°C to 150°C. The SMC MBRB745 operates from -55°C to 150°C, providing 10°C less low-temperature margin. The STPS745G-TR does not specify a minimum temperature but extends the maximum to 175°C. Verify minimum temperature requirements for applications operating below -55°C.