LM2575-12BT Equivalent & Substitute Parts

Part Overview

The LM2575-12BT is a buck switching regulator IC from Microchip Technology designed for step-down voltage conversion with a fixed 12V output and 1A current capacity in a TO-220-5 package. This part is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. Substitute parts must maintain electrical compatibility across input voltage range, output voltage specification, and thermal operating conditions while accommodating packaging and compliance differences.

Substiute Parts

LM2575-12BT

Microchip TechnologyIn Stock: 1070LM2575-12BT Datasheet

Current PartRFQ

LM2575-12WT

Microchip TechnologyIn Stock: 7262LM2575-12WT Datasheet

DirectRFQ

LM2575T-ADJ/NOPB

Texas InstrumentsIn Stock: 6780LM2575T-ADJ/NOPB Datasheet

MFR RecommendedRFQ

LM2596T-12/NOPB

Texas InstrumentsIn Stock: 1000441LM2596T-12/NOPB Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM2575-12BT is determined by the following criteria:

Direct Electrical Compatibility Requirements:

• Step-down (buck) topology with positive output configuration
• Fixed 12V output voltage
• Input voltage range: 4V minimum to 40V maximum
• Output current capacity: minimum 1A
• Operating temperature range: -40°C to 125°C (TJ)
• TO-220-5 package footprint

Substitution Categories:

1. Pin-Compatible Direct Replacement (LM2575-12WT): Identical electrical specifications and package, differing only in product status (active vs. obsolete) and RoHS compliance level.

2. Functional Equivalent with Design Consideration (LM2575T-ADJ/NOPB): Maintains identical topology, frequency, and package but features adjustable output voltage (1.23V to 37V) instead of fixed 12V. Requires external resistor network for 12V configuration.

3. Enhanced Performance Substitute (LM2596T-12/NOPB): Maintains fixed 12V output and TO-220-5 package but increases output current capacity to 3A and switching frequency to 150kHz. Input voltage minimum increased to 4.5V.

Parameter Comparison

Engineering Selection Recommendations

LM2575-12WT (Microchip Technology): This is the primary direct replacement for the obsolete LM2575-12BT. It provides identical electrical performance and package configuration with the advantage of active product status and ROHS3 compliance. Selection of this part eliminates design modifications and maintains full backward compatibility.

LM2575T-ADJ/NOPB (Texas Instruments): This part is suitable when design flexibility for output voltage adjustment is required or when Microchip supply is unavailable. Implementation requires external resistor divider network to establish 12V output. Active product status and ROHS3 compliance are confirmed. This option introduces design complexity through additional passive components.

LM2596T-12/NOPB (Texas Instruments): This part is appropriate for applications requiring output current greater than 1A or when higher switching frequency (150kHz) provides circuit design advantages. The increased current capacity (3A) and higher frequency represent performance enhancements over the original specification. Minimum input voltage increases to 4.5V, which may affect applications operating below this threshold. Active product status and ROHS3 compliance are confirmed.

Frequently Asked Questions (FAQ)

Q: Can LM2575-12WT be used as a direct drop-in replacement for LM2575-12BT?

A: Yes. The LM2575-12WT maintains identical electrical specifications, output voltage (12V fixed), current rating (1A), input voltage range (4V to 40V), switching frequency (52kHz), and TO-220-5 package configuration. No circuit modifications are required.

Q: What is the key difference between LM2575T-ADJ/NOPB and the fixed-output alternatives?

A: The LM2575T-ADJ/NOPB features adjustable output voltage (1.23V to 37V) instead of fixed 12V. To achieve 12V output, external resistors must be added to the feedback network. All other electrical parameters remain compatible with the original specification.

Q: When should LM2596T-12/NOPB be selected instead of LM2575-12WT?

A: The LM2596T-12/NOPB is selected when the application requires output current exceeding 1A or when the higher switching frequency (150kHz vs. 52kHz) provides design benefits such as reduced filter component size. The minimum input voltage requirement increases to 4.5V, which must be verified for the specific application.

Q: Are all substitute parts RoHS compliant?

A: LM2575-12WT, LM2575T-ADJ/NOPB, and LM2596T-12/NOPB are all ROHS3 compliant. The original LM2575-12BT is RoHS non-compliant.

Q: Do the substitute parts maintain the same thermal operating range?

A: Yes. All substitute parts operate across the same junction temperature range of -40°C to 125°C (TJ).

Q: Are there package differences between the substitute parts?

A: LM2575-12WT and LM2575T-ADJ/NOPB use standard TO-220-5 packages. LM2596T-12/NOPB uses TO-220-5 with formed leads. All three maintain the same footprint compatibility for through-hole mounting.