MR751RL Equivalent & Substitute Parts

Part Overview

The MR751RL is a general-purpose rectifier diode manufactured by onsemi, rated for 100 V DC reverse voltage and 6 A average rectified current. The device features a through-hole Microde Button package with standard recovery characteristics and operates across a junction temperature range of -65°C to 175°C. This part is classified as obsolete, necessitating identification of equivalent alternatives for ongoing production and maintenance applications. Substitute parts must maintain electrical compatibility across voltage, current, and thermal specifications while accommodating different physical package formats.

Substiute Parts

MR751RL

onsemiIn Stock: 739MR751RL Datasheet

Current PartRFQ

6A1-TP

Micro Commercial CoIn Stock: 16386A1-TP Datasheet

SimilarRFQ

GI751-E3/54

Vishay General Semiconductor - Diodes DivisionIn Stock: 21962GI751-E3/54 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MR751RL is determined by strict equivalence across the following electrical and mechanical parameters:

Primary Electrical Criteria:

• Voltage - DC Reverse (Vr) (Max): 100 V minimum
• Current - Average Rectified (Io): 6 A minimum
• Voltage - Forward (Vf) (Max) @ If: Compatible within standard rectifier tolerances
• Speed Classification: Standard Recovery >500ns, > 200mA (Io)

Mechanical Criteria:

• Mounting Type: Through Hole
• Package / Case: Axial configuration

Thermal Criteria:

• Operating Temperature - Junction: Must accommodate -65°C to 175°C range or subset thereof

The identified substitute parts 6A1-TP and GI751-E3/54 satisfy these core electrical and mechanical requirements. Both devices are rated for 100 V reverse voltage and 6 A average rectified current with through-hole axial mounting. Differences in package format (R-6 and P600 respectively), forward voltage characteristics, reverse leakage current, and product status are documented in the parameter comparison table below.

Parameter Comparison

Engineering Selection Recommendations

GI751-E3/54 (Vishay General Semiconductor - Diodes Division) is the primary substitute for new applications and ongoing production. This part maintains active product status, carries ROHS3 compliance certification, and demonstrates superior electrical characteristics including lower reverse leakage current (5 µA versus 25 µA) and equivalent forward voltage performance. The P600 package provides mechanical compatibility with through-hole assembly processes. Operating temperature range (-50°C to 150°C) covers the majority of standard industrial applications, with the exception of extended low-temperature operation below -50°C.

6A1-TP (Micro Commercial Co) serves as a secondary substitute where inventory availability or cost considerations are primary factors. This part is classified as "Not For New Designs" and carries ROHS3 compliance. The R-6 package accommodates through-hole mounting with cut-tape packaging. Forward voltage is marginally elevated at 950 mV versus 900 mV, and the operating temperature range (-55°C to 125°C) is more restricted than the primary substitute. This part is suitable for legacy system maintenance and repair applications.

Applications requiring operation below -50°C junction temperature must evaluate thermal performance against the MR751RL's extended lower temperature specification (-65°C).

Frequently Asked Questions (FAQ)

Q: Can GI751-E3/54 directly replace MR751RL in existing circuit boards?

A: Electrical substitution is valid. Both devices are rated for 100 V reverse voltage and 6 A average rectified current with identical forward voltage characteristics (900 mV @ 6 A). Physical package differences exist: MR751RL uses Microde Button format while GI751-E3/54 uses P600 axial package. PCB layout modifications may be required to accommodate the different package geometry.

Q: What is the significance of the "Not For New Designs" status on 6A1-TP?

A: This designation indicates the manufacturer does not recommend this part for new product development. The part remains available for existing applications and maintenance. For new designs, GI751-E3/54 is the preferred selection due to its active product status.

Q: How do reverse leakage current differences affect circuit performance?

A: GI751-E3/54 exhibits 5 µA reverse leakage at 100 V, compared to 25 µA for MR751RL. Lower reverse leakage reduces parasitic current paths and heat generation in high-impedance circuits. For most general-purpose rectification applications, this difference is not functionally significant.

Q: Are there thermal limitations when substituting these parts?

A: MR751RL operates to 175°C junction temperature. GI751-E3/54 is rated to 150°C, and 6A1-TP to 125°C. Applications requiring sustained operation above 150°C junction temperature cannot use GI751-E3/54. Verify thermal design margins in your specific application.

Q: What packaging considerations apply to through-hole assembly?

A: All three parts feature through-hole axial mounting. Physical lead spacing and body diameter differ between Microde Button, R-6, and P600 packages. Verify PCB hole spacing and component clearances before substitution. Cut-tape packaging (6A1-TP and GI751-E3/54) differs from bulk packaging; confirm compatibility with assembly equipment and handling procedures.

Q: Does RoHS compliance affect substitution decisions?

A: MR751RL is RoHS non-compliant. Both substitute parts (6A1-TP and GI751-E3/54) are ROHS3 compliant. If your application or supply chain requires RoHS compliance, substitution is mandatory. Verify compliance requirements with your procurement and regulatory departments.