LM431ACMX Equivalent & Substitute Parts

Part Overview

The LM431ACMX is a shunt voltage reference IC manufactured by Texas Instruments, designed for precision voltage regulation applications. This adjustable reference device operates across a 2.495V to 37V output range with ±2.2% tolerance and supports 100 mA output current. The part is classified as obsolete, which necessitates identification of active equivalent alternatives to ensure design continuity and supply chain reliability for new production and maintenance applications.

Substiute Parts

LM431ACMX

Texas InstrumentsIn Stock: 53220LM431ACMX Datasheet

Current PartRFQ

LM431ACMX/NOPB

Texas InstrumentsIn Stock: 40183LM431ACMX/NOPB Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LM431ACMX is determined by strict equivalence across the following critical parameters:

• Reference Type & Output Type: Both must be shunt-type adjustable voltage references
• Voltage Range: Output voltage capability must span 2.495V to 37V minimum
• Current Rating: Output current must support 100 mA
• Tolerance & Temperature Coefficient: Electrical precision specifications must match ±2.2% tolerance and 50ppm/°C temperature coefficient
• Package & Mounting: Physical form factor must be 8-SOIC surface mount with identical pin configuration
• Cathode Current: Minimum cathode current requirement of 1 mA must be met

The LM431ACMX/NOPB qualifies as a direct substitute based on identical electrical specifications and package configuration. The primary distinction is product status and compliance certification, not functional or electrical parameters.

Parameter Comparison

Engineering Selection Recommendations

The LM431ACMX/NOPB is the direct functional equivalent of the LM431ACMX. Selection between these parts should be based on the following criteria:

For New Designs and Production: The LM431ACMX/NOPB is the appropriate choice. This part carries Active product status, ensuring long-term availability and supply chain stability. It meets ROHS3 compliance requirements, satisfying modern environmental and regulatory standards for electronic components.

For Legacy System Maintenance: The LM431ACMX remains electrically and mechanically compatible with existing designs. However, sourcing may be constrained due to obsolete status. The LM431ACMX/NOPB can be substituted without circuit redesign, as all electrical parameters and package specifications are identical.

Compliance Considerations: The LM431ACMX/NOPB provides superior compliance posture with ROHS3 certification, whereas the original LM431ACMX is RoHS non-compliant. Both parts maintain REACH Unaffected status and EAR99 export classification.

Frequently Asked Questions (FAQ)

Q: Can the LM431ACMX/NOPB be used as a direct replacement for the LM431ACMX?

A: Yes. The LM431ACMX/NOPB is electrically and mechanically identical to the LM431ACMX. All critical parameters—voltage range, current rating, tolerance, temperature coefficient, and 8-SOIC package configuration—are equivalent. No circuit modifications are required.

Q: What is the difference between LM431ACMX and LM431ACMX/NOPB?

A: The primary differences are product status and compliance certification. The LM431ACMX is obsolete and RoHS non-compliant, while the LM431ACMX/NOPB is active and ROHS3 compliant. The "/NOPB" suffix indicates lead-free, halogen-free packaging. Electrical performance is identical.

Q: Are there packaging differences between these parts?

A: Both parts use the same 8-SOIC (0.154", 3.90mm Width) surface mount package. The LM431ACMX is supplied in bulk packaging, while the LM431ACMX/NOPB is supplied in Tape & Reel format, which is standard for automated assembly processes.

Q: What parameters must match for a valid substitution?

A: Valid substitution requires equivalence in reference type (shunt), output type (adjustable), voltage range (2.495V to 37V), current rating (100 mA), tolerance (±2.2%), temperature coefficient (50ppm/°C), cathode current (1 mA), operating temperature range (0°C to 70°C), and package configuration (8-SOIC surface mount).

Q: Is the LM431ACMX/NOPB suitable for new product designs?

A: Yes. The LM431ACMX/NOPB is the recommended choice for new designs. Active product status ensures availability, and ROHS3 compliance aligns with current regulatory requirements and industry standards.