LM2940IMP-12 Linear Voltage Regulator - Equivalent & Substitute Parts

Part Overview

The LM2940IMP-12 is a linear voltage regulator IC from Texas Instruments designed for positive fixed 12V output at 1A current capacity in a SOT-223-4 surface mount package. This part is classified as obsolete, making equivalent and substitute parts necessary for new designs and ongoing production requirements. The device provides regulated 12V output from input voltages up to 26V with integrated protection features including over-current, over-temperature, reverse polarity, and short-circuit protection.

Substiute Parts

LM2940IMP-12

Texas InstrumentsIn Stock: 1000326LM2940IMP-12 Datasheet

Current PartRFQ

LM2940IMP-12/NOPB

Texas InstrumentsIn Stock: 3329LM2940IMP-12/NOPB Datasheet

Parametric EquivalentRFQ

LM2940IMPX-12/NOPB

Texas InstrumentsIn Stock: 2328LM2940IMPX-12/NOPB Datasheet

Parametric EquivalentRFQ

MIC2920A-12WS

Microchip TechnologyIn Stock: 4810MIC2920A-12WS Datasheet

MFR RecommendedRFQ

MIC2920A-12WS-TR

Microchip TechnologyIn Stock: 7990MIC2920A-12WS-TR Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the LM2940IMP-12 are classified into two categories based on parametric equivalence and manufacturer recommendations:

Parametric Equivalents (Texas Instruments LM2940 Series): Parts LM2940IMP-12/NOPB and LM2940IMPX-12/NOPB maintain identical electrical specifications to the main part, including 12V fixed output, 1A output current, 26V maximum input voltage, and 1V maximum dropout voltage. These parts differ only in product status (Active vs. Obsolete) and RoHS compliance (ROHS3 Compliant vs. non-compliant). Both use the same SOT-223-4 package and are direct functional replacements.

Manufacturer Recommended Alternatives (Microchip MIC2920A Series): Parts MIC2920A-12WS and MIC2920A-12WS-TR are manufacturer-recommended substitutes with the same 12V fixed output and 26V maximum input voltage. These parts operate at reduced output current (400mA vs. 1A) and feature improved dropout voltage (0.75V @ 400mA), lower quiescent current (300 µA vs. 10 mA), and extended operating temperature range (-40°C to 125°C). The package type is SOT-223-3 (three pins vs. four pins).

Key Parameters Determining Substitution:

• Output voltage: 12V (fixed)
• Input voltage rating: 26V maximum
• Output configuration: Positive
• Mounting type: Surface mount
• Package compatibility: SOT-223 family

Parameter Comparison

Engineering Selection Recommendations

For applications requiring direct replacement of the LM2940IMP-12 with identical electrical performance and 1A output current capacity, select either LM2940IMP-12/NOPB or LM2940IMPX-12/NOPB. Both parts are active products with ROHS3 compliance, addressing the obsolescence and regulatory compliance limitations of the original part.

For applications where output current requirements do not exceed 400mA, the Microchip MIC2920A-12WS or MIC2920A-12WS-TR offer advantages including lower quiescent current consumption, improved dropout voltage performance, and extended operating temperature range to 125°C. These parts are suitable for power-sensitive applications and environments requiring higher temperature operation.

Selection between packaging options (Cut Tape & Digi-Reel vs. Tube) depends on procurement and assembly requirements. The SOT-223-3 package used by Microchip parts reduces pin count compared to the SOT-223-4 package of Texas Instruments regulators, requiring PCB layout modification.

Frequently Asked Questions (FAQ)

Q: Can LM2940IMP-12/NOPB directly replace LM2940IMP-12 in existing designs?

A: Yes. LM2940IMP-12/NOPB is a parametric equivalent with identical electrical specifications, output voltage, output current, input voltage rating, dropout voltage, and SOT-223-4 package. The primary differences are active product status and ROHS3 compliance.

Q: What are the limitations of using MIC2920A-12WS as a substitute?

A: The MIC2920A-12WS reduces maximum output current from 1A to 400mA and uses a SOT-223-3 package instead of SOT-223-4. Applications requiring full 1A output current or those with existing PCB layouts designed for four-pin packages require design modification. This substitute is suitable only for applications with output current requirements of 400mA or less.

Q: Are all substitute parts RoHS compliant?

A: LM2940IMP-12/NOPB, LM2940IMPX-12/NOPB, MIC2920A-12WS, and MIC2920A-12WS-TR are all ROHS3 compliant. The original LM2940IMP-12 is RoHS non-compliant.

Q: What is the difference between LM2940IMP-12/NOPB and LM2940IMPX-12/NOPB?

A: Both parts are parametric equivalents with identical electrical specifications and package type. The difference lies in packaging format: LM2940IMP-12/NOPB is supplied in Cut Tape & Digi-Reel format, while LM2940IMPX-12/NOPB is also available in Cut Tape & Digi-Reel format. Selection depends on procurement and assembly line requirements.

Q: Can MIC2920A-12WS-TR be used interchangeably with MIC2920A-12WS?

A: Both parts have identical electrical specifications and SOT-223-3 package. The difference is packaging format: MIC2920A-12WS is supplied in Tube, while MIC2920A-12WS-TR is supplied in Cut Tape & Digi-Reel. Selection depends on assembly process requirements.

Q: What is the impact of the lower quiescent current in MIC2920A parts?

A: The MIC2920A series draws 300 µA quiescent current compared to 10 mA in the LM2940 series. This 33-fold reduction benefits battery-powered and low-power standby applications by reducing idle power consumption.