LM2931CMX Linear Voltage Regulator Equivalent & Substitute Parts

Part Overview

The LM2931CMX is a linear voltage regulator IC from Texas Instruments designed for positive adjustable output applications. It delivers 100mA output current in an 8-SOIC surface mount package with input voltage range up to 26V and adjustable output from 3V to 24V. The device includes protection features for over temperature, reverse polarity, and short circuit conditions.

This part is currently in Last Time Buy status, making equivalent and substitute parts essential for ongoing design support and procurement planning. Substitute parts maintain functional compatibility while offering extended availability and alternative manufacturer options.

Substiute Parts

LM2931CMX

Texas InstrumentsIn Stock: 6510LM2931CMX Datasheet

Current PartRFQ

LM2931CMX/NOPB

Texas InstrumentsIn Stock: 2217LM2931CMX/NOPB Datasheet

Parametric EquivalentRFQ

LM2931ACDR2G

onsemiIn Stock: 30256LM2931ACDR2G Datasheet

MFR RecommendedRFQ

LM2931CDR2G

onsemiIn Stock: 10290LM2931CDR2G Datasheet

MFR RecommendedRFQ

NCV2931ACDR2G

onsemiIn Stock: 19684NCV2931ACDR2G Datasheet

MFR RecommendedRFQ

NCV2931CDR2G

onsemiIn Stock: 2095NCV2931CDR2G Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the LM2931CMX is determined by the following critical parameters:

• Output Configuration & Type: Positive adjustable output with 1 regulator
• Electrical Performance: 100mA output current, 26V maximum input voltage, adjustable output range
• Package Compatibility: 8-SOIC surface mount package with identical 3.90mm width
• Protection Features: Over temperature and short circuit protection
• Compliance: ROHS3 compliance and MSL Level 1

Substitute parts are grouped into two categories:

Category 1 - Direct Parametric Equivalents (Texas Instruments)

• LM2931CMX/NOPB: Identical electrical specifications and packaging from the same manufacturer

Category 2 - Functional Equivalents (onsemi)

• LM2931ACDR2G, LM2931CDR2G, NCV2931ACDR2G, NCV2931CDR2G: Maintain core functionality with compatible electrical parameters and identical package form factor. onsemi variants offer extended temperature range (-40°C ~ 125°C) and higher maximum output voltage (29.5V) compared to the original specification.

Parameter Comparison

Engineering Selection Recommendations

For Direct Replacement (No Design Changes Required)

LM2931CMX/NOPB from Texas Instruments provides identical electrical specifications and operating parameters. This part maintains the original -40°C ~ 85°C temperature range and 0.3V dropout specification. Selection is appropriate when design specifications require exact parameter matching and Texas Instruments sourcing is preferred.

For Extended Availability (Design Margin Acceptable)

onsemi LM2931ACDR2G and LM2931CDR2G offer active product status with significantly higher inventory levels (30,200 and 10,200 units respectively). These parts feature extended operating temperature range (-40°C ~ 125°C) and higher maximum output voltage (29.5V vs. 24V). The increased dropout voltage (0.6V vs. 0.3V) requires verification against circuit design margins. Selection is appropriate when temperature performance headroom or extended availability is prioritized.

For Automotive Applications

NCV2931ACDR2G and NCV2931CDR2G from onsemi carry AEC-Q100 automotive qualification. These parts are suitable for automotive-grade designs requiring formal qualification documentation. Electrical parameters are identical to the standard LM2931 onsemi variants.

Packaging Considerations

All substitute parts maintain 8-SOIC package compatibility. Packaging format variations (Cut Tape, Digi-Reel, Tape & Reel) do not affect electrical performance and are determined by procurement and assembly requirements.

Frequently Asked Questions (FAQ)

Q: Can LM2931CMX/NOPB be used as a direct drop-in replacement for LM2931CMX?

A: Yes. LM2931CMX/NOPB maintains identical electrical specifications, operating temperature range, and package form factor. The only difference is packaging format (Cut Tape & Digi-Reel vs. standard packaging). No circuit modifications are required.

Q: What are the key differences between Texas Instruments and onsemi variants?

A: onsemi variants (LM2931ACDR2G, LM2931CDR2G, NCV2931ACDR2G, NCV2931CDR2G) offer extended operating temperature range (-40°C ~ 125°C vs. -40°C ~ 85°C), higher maximum output voltage (29.5V vs. 24V), and lower quiescent current supply (6 mA vs. 15 mA). Dropout voltage increases from 0.3V to 0.6V at 100mA. These differences must be evaluated against circuit design requirements.

Q: Are onsemi parts suitable for designs originally specified for LM2931CMX?

A: onsemi parts are functionally compatible when circuit design margins accommodate the increased dropout voltage (0.6V vs. 0.3V) and extended temperature range does not conflict with application requirements. Verify that output voltage adjustment range (2.7V to 29.5V) meets circuit specifications.

Q: What is the difference between NCV2931 and LM2931 onsemi variants?

A: NCV2931ACDR2G and NCV2931CDR2G carry AEC-Q100 automotive qualification. Electrical specifications are identical to LM2931ACDR2G and LM2931CDR2G. Selection depends on automotive qualification requirements.

Q: Can these parts be used interchangeably in the same PCB assembly?

A: Yes. All substitute parts use identical 8-SOIC package pinout and footprint. PCB layout and schematic connections require no modification. Packaging format (Cut Tape, Digi-Reel, Tape & Reel) affects only procurement and assembly handling.

Q: Which substitute part offers the best availability?

A: LM2931ACDR2G from onsemi provides the highest inventory level at 30,200 units. This part is recommended when extended availability and procurement continuity are primary concerns.

Q: Are all substitute parts RoHS3 compliant?

A: Yes. All listed substitute parts maintain ROHS3 compliance and MSL Level 1 (Unlimited) moisture sensitivity rating, matching the original LM2931CMX specifications.