LM2576-12BT Equivalent & Substitute Parts

Part Overview

The LM2576-12BT is a buck switching regulator IC from Microchip Technology, designed for step-down voltage conversion with a fixed 12V output at 3A maximum current. This device operates across a wide input voltage range of 4V to 40V and is housed in a TO-220-5 through-hole package. The part is currently classified as obsolete, making identification of suitable alternatives essential for ongoing design support and production continuity.

Substiute Parts

LM2576-12BT

Microchip TechnologyIn Stock: 4349LM2576-12BT Datasheet

Current PartRFQ

LM2576-12WT

Microchip TechnologyIn Stock: 1114LM2576-12WT Datasheet

DirectRFQ

LM2576T-ADJ/NOPB

Texas InstrumentsIn Stock: 50286LM2576T-ADJ/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM2576-12BT is determined by strict alignment of electrical and mechanical parameters. The critical criteria for equivalence are:

• Topology & Function: Buck (step-down) switching regulator
• Output Configuration: Positive output
• Package Type: TO-220-5 through-hole mounting
• Switching Frequency: 52kHz
• Input Voltage Range: 4V to 40V minimum
• Output Current Capability: 3A minimum
• Operating Temperature Range: -40°C to 125°C minimum

Two substitute parts meet these criteria with varying output voltage configurations:

1. LM2576-12WT (Microchip Technology): Direct equivalent with identical fixed 12V output specification and active product status
2. LM2576T-ADJ/NOPB (Texas Instruments): Functionally compatible with adjustable output voltage capability, allowing 12V configuration through external resistor network

Parameter Comparison

Engineering Selection Recommendations

LM2576-12WT is the primary substitute for the obsolete LM2576-12BT. Both parts are manufactured by Microchip Technology with identical electrical specifications and fixed 12V output configuration. The LM2576-12WT carries active product status and ROHS3 compliance, providing long-term availability and regulatory alignment for new designs and production continuity.

LM2576T-ADJ/NOPB from Texas Instruments is a functionally compatible alternative with adjustable output voltage capability. While this part requires external resistor configuration to achieve 12V output, it offers the advantage of active product status, ROHS3 compliance, and significantly higher inventory availability (50,200 units). Selection of this part is appropriate when design flexibility for output voltage adjustment is beneficial or when supply chain considerations favor Texas Instruments sourcing.

Both substitute parts maintain electrical equivalence across input voltage range, output current rating, switching frequency, and thermal operating range. Package compatibility is identical (TO-220-5 through-hole), ensuring direct mechanical substitution without PCB redesign.

Frequently Asked Questions (FAQ)

Q: Can LM2576-12WT be used as a direct replacement for LM2576-12BT?

A: Yes. The LM2576-12WT is a direct equivalent with identical electrical specifications, fixed 12V output, 3A current rating, and TO-220-5 package. The primary difference is product status (active vs. obsolete) and RoHS compliance (ROHS3 vs. non-compliant).

Q: What is the difference between LM2576-12WT and LM2576T-ADJ/NOPB?

A: The LM2576-12WT provides fixed 12V output, while the LM2576T-ADJ/NOPB has adjustable output voltage (1.23V to 37V). Both share identical input range, output current, switching frequency, and package. The adjustable version requires external resistor network configuration to set output voltage to 12V.

Q: Are there any package or pinout differences between these parts?

A: No. All three parts use the TO-220-5 through-hole package with identical pinout, enabling direct mechanical substitution without PCB modification.

Q: Which substitute should be selected for new designs?

A: LM2576-12WT is recommended for designs requiring fixed 12V output with Microchip sourcing. LM2576T-ADJ/NOPB is suitable when Texas Instruments sourcing is preferred or when adjustable output voltage capability provides design flexibility.

Q: Are both substitutes RoHS compliant?

A: Yes. Both LM2576-12WT and LM2576T-ADJ/NOPB are ROHS3 compliant. The original LM2576-12BT is RoHS non-compliant due to its obsolete status.

Q: What is the switching frequency of these regulators?

A: All three parts operate at 52kHz switching frequency, ensuring compatibility in applications with frequency-dependent filtering or noise considerations.