MIC4451BM Low-Side Gate Driver IC Equivalent & Substitute Parts

Part Overview

The MIC4451BM is a low-side gate driver IC manufactured by Microchip Technology, designed for driving IGBT and N-Channel MOSFET applications. This inverting gate driver operates from a 4.5V to 18V supply and delivers 12A peak output current in both source and sink configurations. The device is packaged in an 8-SOIC surface mount package with a 3.90mm width.

The MIC4451BM is currently discontinued at DiGi Electronics, making equivalent substitute parts necessary for ongoing production and maintenance applications. Identifying compatible alternatives ensures design continuity and supply chain resilience.

Substiute Parts

MIC4451BM

Microchip TechnologyIn Stock: 1319MIC4451BM Datasheet

Current PartRFQ

MIC4451YM

Microchip TechnologyIn Stock: 2115MIC4451YM Datasheet

DirectRFQ

UCC37321D

Texas InstrumentsIn Stock: 1203UCC37321D Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the MIC4451BM is determined by the following critical parameters:

Primary Substitution Criteria:

• Driven Configuration: Low-Side (must match exactly)
• Channel Type: Single (must match exactly)
• Number of Drivers: 1 (must match exactly)
• Input Type: Inverting (must match exactly)
• Package / Case: 8-SOIC with 3.90mm width (must match exactly)
• Mounting Type: Surface Mount (must match exactly)

Electrical Compatibility Parameters:

• Gate Type: IGBT and/or N-Channel MOSFET capability
• Voltage - Supply: Must support the application's supply voltage range
• Current - Peak Output: Must meet or exceed the required source and sink current demands
• Logic Voltage Thresholds: Must be compatible with the control signal levels
• Operating Temperature Range: Must cover the application's thermal requirements

The MIC4451YM (Microchip Technology) and UCC37321D (Texas Instruments) meet the primary substitution criteria. Both devices maintain the same driven configuration, channel topology, input type, and package specifications as the MIC4451BM.

Parameter Comparison

Engineering Selection Recommendations

MIC4451YM (Microchip Technology) is the primary substitute for the MIC4451BM. Both devices are from the same manufacturer and share identical electrical specifications, including supply voltage range (4.5V ~ 18V), peak output current (12A source and sink), logic voltage thresholds (0.8V, 2.4V), and operating temperature range (-40°C ~ 85°C). The MIC4451YM is currently in active production status with ROHS3 compliance, providing superior long-term availability and regulatory alignment compared to the discontinued MIC4451BM.

UCC37321D (Texas Instruments) is a secondary substitute option. This device maintains the same package, driven configuration, and input type as the MIC4451BM. However, electrical differences exist: the UCC37321D operates from 4V to 15V (narrower than the MIC4451BM's 4.5V ~ 18V range), delivers 9A peak output current (lower than the MIC4451BM's 12A), features different logic voltage thresholds (1.1V, 2.7V), and supports a reduced operating temperature range (0°C ~ 70°C versus -40°C ~ 85°C). The UCC37321D is designated as Last Time Buy, indicating limited future availability. Selection of the UCC37321D requires verification that the application's supply voltage, output current requirements, logic signal levels, and thermal operating conditions fall within its specified ranges.

Frequently Asked Questions (FAQ)

Q: Can the MIC4451YM directly replace the MIC4451BM without PCB modifications?

A: Yes. The MIC4451YM is a direct pin-compatible substitute with identical electrical specifications and the same 8-SOIC package footprint. No PCB layout changes are required.

Q: What are the key differences between the MIC4451YM and UCC37321D?

A: The primary differences are supply voltage range (MIC4451YM: 4.5V ~ 18V versus UCC37321D: 4V ~ 15V), peak output current (MIC4451YM: 12A versus UCC37321D: 9A), logic voltage thresholds (MIC4451YM: 0.8V/2.4V versus UCC37321D: 1.1V/2.7V), and operating temperature range (MIC4451YM: -40°C ~ 85°C versus UCC37321D: 0°C ~ 70°C). Applications requiring the full supply voltage range, higher output current, or extended temperature operation must use the MIC4451YM.

Q: Is the UCC37321D suitable for applications currently using the MIC4451BM?

A: The UCC37321D is suitable only if the application's supply voltage remains within 4V to 15V, the required peak output current does not exceed 9A, the logic signal levels are compatible with 1.1V/2.7V thresholds, and the operating temperature stays within 0°C to 70°C. Applications requiring the full 4.5V ~ 18V supply range or -40°C ~ 85°C temperature operation must use the MIC4451YM.

Q: Why is the MIC4451BM discontinued?

A: The MIC4451BM is discontinued at DiGi Electronics. The MIC4451YM, also from Microchip Technology, is the active production equivalent and is recommended for all new designs and ongoing production requirements.

Q: Are both substitute parts RoHS compliant?

A: Yes. Both the MIC4451YM and UCC37321D are ROHS3 compliant, whereas the original MIC4451BM is RoHS non-compliant. This provides improved regulatory alignment for new applications.

Q: What is the package compatibility between these devices?

A: All three devices (MIC4451BM, MIC4451YM, and UCC37321D) use the 8-SOIC package with 3.90mm width. They are mechanically and electrically compatible at the package level, enabling direct PCB substitution without layout modifications.