LM2576-3.3BT Equivalent & Substitute Parts

Part Overview

The LM2576-3.3BT is a buck switching regulator IC from Microchip Technology designed for step-down voltage conversion with a fixed 3.3V output and 3A current capacity. This component operates across a wide input voltage range of 4V to 40V and is housed in a TO-220-5 package for through-hole mounting applications. The part is currently classified as obsolete, making identification of functionally equivalent alternatives essential for ongoing design support and production continuity.

Substiute Parts

LM2576-3.3BT

Microchip TechnologyIn Stock: 2291LM2576-3.3BT Datasheet

Current PartRFQ

LM2576-3.3WT

Microchip TechnologyIn Stock: 4132LM2576-3.3WT Datasheet

DirectRFQ

AP1501-33T5L-U

Diodes IncorporatedIn Stock: 1952AP1501-33T5L-U Datasheet

MFR RecommendedRFQ

LM2591HVT-3.3/NOPB

Texas InstrumentsIn Stock: 2169LM2591HVT-3.3/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM2576-3.3BT is determined by the following critical parameters:

• Output Voltage: Must be fixed at 3.3V
• Package Type: Must be TO-220-5 for mechanical and thermal compatibility
• Topology: Must be buck (step-down) configuration
• Output Configuration: Must be positive output
• Number of Outputs: Must be single output
• Mounting Type: Must be through-hole

Substitute parts are grouped into two categories:

Direct Substitutes (Same Manufacturer): Parts from Microchip Technology with identical electrical specifications and packaging, differing only in product status or compliance certifications.

Cross-Manufacturer Equivalents: Parts from alternative manufacturers (Diodes Incorporated, Texas Instruments) that meet the core electrical and mechanical requirements, though with variations in output current capacity or switching frequency that remain within acceptable design parameters.

Parameter Comparison

Engineering Selection Recommendations

LM2576-3.3WT (Microchip Technology): This is the primary direct substitute for the LM2576-3.3BT. It maintains identical electrical specifications and packaging while offering active product status and RoHS3 compliance. This part is recommended for designs requiring direct compatibility with existing layouts and thermal management strategies. Inventory availability is higher than the original part.

AP1501-33T5L-U (Diodes Incorporated): This cross-manufacturer equivalent provides 3A output current capacity and fixed 3.3V output in a TO-220-5L package. It is RoHS3 compliant and actively supported. This option is suitable for applications where manufacturer diversification is acceptable and where the TO-220-5L package variant is compatible with existing PCB designs.

LM2591HVT-3.3/NOPB (Texas Instruments): This part offers a higher input voltage range (4.5V to 60V) and higher switching frequency (150kHz), which may provide improved efficiency in certain applications. However, the output current is limited to 1A, making this option unsuitable for designs requiring the full 3A capacity of the original part. This substitute is only appropriate for applications with reduced current requirements.

Frequently Asked Questions (FAQ)

Q: Can the LM2576-3.3WT be used as a direct replacement for the LM2576-3.3BT?

A: Yes. The LM2576-3.3WT is electrically and mechanically identical to the LM2576-3.3BT, with the same output voltage (3.3V), output current (3A), input voltage range (4V to 40V), switching frequency (52kHz), and TO-220-5 package. The primary differences are product status (active vs. obsolete) and RoHS compliance (RoHS3 vs. non-compliant).

Q: What is the key limitation of the LM2591HVT-3.3/NOPB as a substitute?

A: The LM2591HVT-3.3/NOPB has a maximum output current of 1A, compared to the 3A capacity of the LM2576-3.3BT. This part is only suitable for applications requiring 1A or less. For designs requiring the full 3A output, this substitute is not appropriate.

Q: Are there package compatibility considerations between TO-220-5 and TO-220-5L?

A: The TO-220-5L variant (used by AP1501-33T5L-U) features formed leads, which may require PCB layout adjustments compared to standard TO-220-5 packages. Verify that the formed lead configuration is compatible with existing through-hole pad spacing and mounting hardware before selection.

Q: Why is RoHS compliance important for this substitution?

A: The original LM2576-3.3BT is RoHS non-compliant. If the application or supply chain requires RoHS3 compliance, the LM2576-3.3WT, AP1501-33T5L-U, or LM2591HVT-3.3/NOPB are compliant alternatives. Verify compliance requirements with your procurement and regulatory teams.

Q: Can the AP1501-33T5L-U be used in all applications where the LM2576-3.3BT was used?

A: The AP1501-33T5L-U maintains the same output voltage (3.3V) and current (3A) specifications. However, the TO-220-5L package with formed leads may require PCB layout verification. Additionally, unspecified input voltage range and switching frequency parameters should be confirmed against your application requirements before implementation.