Equivalent & Substitute Parts for 173-473LAF-301

Part Overview

The 173-473LAF-301 is an NTC thermistor manufactured by Honeywell Sensing and Productivity Solutions, rated at 47kΩ resistance at 25°C with a B-value of 4150K. This surface-mount component in 0805 (2012 Metric) package is designed for temperature sensing applications across the -60°C to 125°C operating range. The product is classified as Obsolete, necessitating identification of functionally equivalent alternatives for ongoing production and maintenance applications.

Substiute Parts

173-473LAF-301

Honeywell Sensing and Productivity SolutionsIn Stock: 823173-473LAF-301 Datasheet

Current PartRFQ

NCP21WB473J03RA

Murata ElectronicsIn Stock: 92646NCP21WB473J03RA Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the 173-473LAF-301 is determined by the following mandatory criteria:

Electrical Parameters:

• Resistance value must be 47kΩ at 25°C
• Resistance tolerance must be ±5% or tighter
• B-value characteristics must be compatible with the thermal response profile (B25/85 range of 4050K to 4150K acceptable)

Physical Parameters:

• Package must be 0805 (2012 Metric) surface-mount configuration
• Mounting type must be surface mount

Environmental & Compliance:

• Operating temperature range must encompass -60°C to 125°C or provide coverage within the application's required subset
• RoHS compliance status must be maintained

Identified Substitute: The NCP21WB473J03RA from Murata Electronics meets all mandatory substitution criteria. This component shares the identical 47kΩ resistance specification, 0805 package form factor, and surface-mount configuration. The B-value tolerance of ±3% and B25/85 specification of 4108K fall within acceptable thermal response parameters. Operating temperature range of -40°C to 125°C covers the critical upper range of the original specification.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: NCP21WB473J03RA

The NCP21WB473J03RA is the qualified equivalent for the 173-473LAF-301 based on the following engineering criteria:

Electrical Compatibility: All core electrical specifications align. The 47kΩ resistance and ±5% tolerance are identical. The B25/85 value of 4108K differs from the original 4150K by approximately 1%, which is within acceptable thermal response variance for NTC thermistor applications where B-value tolerance is ±3%.

Physical Compatibility: Both components utilize the 0805 (2012 Metric) surface-mount package, ensuring direct PCB footprint compatibility without layout modifications.

Environmental Compliance: The Murata component maintains RoHS3 compliance, exceeding the original RoHS requirement. Moisture Sensitivity Level 1 (Unlimited) matches the original specification.

Temperature Range Consideration: The Murata substitute operates from -40°C to 125°C. Applications requiring operation below -40°C must evaluate whether the -60°C lower limit of the original component is functionally necessary. For applications within the -40°C to 125°C range, the substitute provides full coverage.

Product Status: Both components carry legacy product status (Obsolete vs. Not For New Designs), indicating limited long-term availability. Inventory assessment shows 92,579 units of the Murata substitute available, compared to 744 units of the original component.

Frequently Asked Questions (FAQ)

Q: Can the NCP21WB473J03RA be used as a direct replacement for the 173-473LAF-301?

A: Yes, for applications operating within -40°C to 125°C. The components share identical resistance specifications (47kΩ ±5%), package form factor (0805 surface mount), and mounting type. The B-value difference of 1% (4108K vs. 4150K) is within acceptable thermal response parameters for NTC thermistor applications.

Q: What is the significance of the B-value difference between 4150K and 4108K?

A: The B-value defines the temperature coefficient of the thermistor. A 1% difference (42K variance) represents minimal thermal response deviation. For most temperature sensing applications, this variance is negligible. Applications requiring precise thermal matching within ±0.5°C should conduct thermal calibration testing.

Q: Does the operating temperature range difference affect substitution?

A: The original component specifies -60°C to 125°C; the substitute covers -40°C to 125°C. If your application requires operation below -40°C, the substitute is not suitable. For applications within -40°C to 125°C, the substitute provides full operational coverage.

Q: Are there PCB layout changes required?

A: No. Both components use the 0805 (2012 Metric) surface-mount package. PCB footprints, solder pad dimensions, and assembly processes remain identical.

Q: What is the difference between RoHS and ROHS3 compliance?

A: ROHS3 represents the current European Union RoHS Directive 2011/65/EU standard, which supersedes earlier RoHS versions. ROHS3 compliance ensures the component meets current environmental regulations and is preferred for new applications.

Q: Why is the Murata component marked "Not For New Designs"?

A: This designation indicates the manufacturer is not recommending the component for new product development, typically due to product maturity or planned discontinuation. However, it remains available for replacement and maintenance applications. For new designs, consult Murata's current NTC thermistor portfolio.

Q: What inventory considerations should guide the substitution decision?

A: The Murata substitute (NCP21WB473J03RA) has 92,579 units in stock compared to 744 units of the original component. For production quantities or long-term maintenance requirements, the substitute offers significantly better supply availability.