LM4140BCMX-4.1 Equivalent & Substitute Parts

Part Overview

The LM4140BCMX-4.1 is a Series Voltage Reference IC manufactured by Texas Instruments, designed to provide a fixed 4.096V output with ±0.1% tolerance. This component is classified as obsolete, which necessitates identification of equivalent and substitute parts for ongoing design requirements and production continuity. The part operates across a 1.8V to 5.5V input range with 8mA output current capability and is housed in an 8-SOIC surface mount package.

Substiute Parts

LM4140BCMX-4.1

Texas InstrumentsIn Stock: 786LM4140BCMX-4.1 Datasheet

Current PartRFQ

LM4140BCMX-4.1/NOPB

National SemiconductorIn Stock: 1773LM4140BCMX-4.1/NOPB Datasheet

DirectRFQ

LTC1798CS8-4.1#PBF

Analog Devices Inc.In Stock: 1238LTC1798CS8-4.1#PBF Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the LM4140BCMX-4.1 is determined by the following critical parameters:

• Fixed output voltage of 4.096V
• 8-SOIC surface mount package form factor
• Input voltage range compatibility (1.8V ~ 5.5V minimum requirement)
• Output current capability (minimum 8mA)
• Operating temperature range (0°C ~ 70°C)
• Tolerance specification (±0.1% or better)

Substitute parts must maintain electrical compatibility across these parameters while accommodating minor variations in secondary characteristics such as temperature coefficient, noise performance, and supply current, provided the primary functional requirements are satisfied.

Parameter Comparison

Engineering Selection Recommendations

The LM4140BCMX-4.1/NOPB represents a direct functional equivalent, maintaining identical electrical specifications including ±0.1% tolerance, 6ppm/°C temperature coefficient, and 2.2µVp-p noise performance. This part is currently in active production status and is available in bulk packaging, making it the primary choice for direct replacement in existing designs.

The LTC1798CS8-4.1#PBF is a manufacturer-recommended alternative from Analog Devices Inc. This part maintains the 4.096V fixed output and 8-SOIC package compatibility but introduces specification variations: ±0.15% tolerance (versus ±0.1%), 40ppm/°C temperature coefficient (versus 6ppm/°C), and 8µVp-p noise (versus 2.2µVp-p). The input voltage range extends to 12.6V maximum and supply current is significantly reduced to 8.5µA. This part is ROHS3 compliant, addressing environmental compliance requirements. Selection of this alternative is appropriate when the relaxed tolerance and temperature coefficient specifications are acceptable for the application and when extended input voltage range or reduced supply current provides system-level benefits.

Frequently Asked Questions (FAQ)

Q: Can the LTC1798CS8-4.1#PBF be used as a direct replacement for the LM4140BCMX-4.1?

A: The LTC1798CS8-4.1#PBF maintains the same fixed output voltage (4.096V), output current capability (10mA exceeds the 8mA requirement), and 8-SOIC package form factor. However, it introduces relaxed tolerance (±0.15% versus ±0.1%), higher temperature coefficient (40ppm/°C versus 6ppm/°C), and increased noise (8µVp-p versus 2.2µVp-p). Substitution is valid only when these specification changes are acceptable for the application.

Q: What is the primary difference between the LM4140BCMX-4.1/NOPB and the main part?

A: The LM4140BCMX-4.1/NOPB is electrically and functionally identical to the LM4140BCMX-4.1, with the primary distinction being active production status versus obsolete status. Both parts share identical electrical specifications and package configuration.

Q: Are all three parts compatible with the same PCB layout?

A: Yes. All three parts use the 8-SOIC (0.154", 3.90mm Width) surface mount package, ensuring mechanical and footprint compatibility on the same printed circuit board layout.

Q: What input voltage range must be considered when selecting a substitute?

A: The LM4140BCMX-4.1 and LM4140BCMX-4.1/NOPB require input voltage between 1.8V and 5.5V. The LTC1798CS8-4.1#PBF requires input voltage between 4.296V and 12.6V. Selection must ensure the system supply voltage falls within the specified range of the chosen part.

Q: Does RoHS compliance affect substitution decisions?

A: The main part and LM4140BCMX-4.1/NOPB are RoHS non-compliant, while the LTC1798CS8-4.1#PBF is ROHS3 compliant. If RoHS compliance is a design requirement, the LTC1798CS8-4.1#PBF is the appropriate selection, provided its electrical specification variations are acceptable.