LR253K0F Equivalent & Substitute Parts

Part Overview

The LR253K0F is an NTC thermistor manufactured by Littelfuse Inc., rated at 25kΩ resistance with ±1% tolerance in a 1206 (3216 Metric) surface mount package. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing production and maintenance applications. The thermistor operates across a temperature range of -40°C to 125°C with a maximum power dissipation of 400 mW, serving temperature sensing and compensation functions in electronic circuits.

Substiute Parts

LR253K0F

Littelfuse Inc.In Stock: 727LR253K0F Datasheet

Current PartRFQ

SM253K0F-2

Littelfuse Inc.In Stock: 806SM253K0F-2 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the LR253K0F is determined by the following critical parameters:

• Resistance value: 25kΩ at 25°C
• Resistance tolerance: ±1%
• Package type: 1206 (3216 Metric) surface mount
• Operating temperature range: -40°C to 125°C
• Power dissipation capability: 400 mW minimum
• RoHS3 compliance and REACH unaffected status

The SM253K0F-2 qualifies as a direct substitute based on matching all specified electrical and mechanical parameters. Both components are manufactured by Littelfuse Inc., ensuring consistency in thermistor characteristics and performance within the defined operating envelope.

Parameter Comparison

Engineering Selection Recommendations

The SM253K0F-2 is the recommended substitute for the obsolete LR253K0F. Both components maintain identical electrical specifications, mechanical packaging, and regulatory compliance profiles. The SM253K0F-2 carries active product status, ensuring continued availability and supply chain reliability. Both parts satisfy ROHS3 compliance requirements and maintain REACH unaffected classification, supporting regulatory requirements for modern manufacturing environments. The transition from LR253K0F to SM253K0F-2 requires no circuit modifications or thermal management adjustments, as all critical parameters remain equivalent.

Frequently Asked Questions (FAQ)

Q: Can SM253K0F-2 be used as a direct replacement for LR253K0F in existing designs?

A: Yes. Both components share identical resistance values (25kΩ), tolerance specifications (±1%), operating temperature ranges (-40°C to 125°C), power ratings (400 mW), and 1206 (3216 Metric) surface mount packaging. No design modifications are required.

Q: What is the significance of the product status change from Obsolete to Active?

A: The LR253K0F is classified as obsolete, indicating discontinued production. The SM253K0F-2 maintains active status, ensuring ongoing manufacturing availability and supply chain continuity for new production runs and field replacements.

Q: Are there any compliance differences between these parts?

A: No. Both components are ROHS3 compliant and REACH unaffected, meeting identical regulatory requirements for environmental and hazardous substance restrictions.

Q: Does the 1206 package ensure PCB compatibility?

A: Yes. Both the LR253K0F and SM253K0F-2 use the 1206 (3216 Metric) surface mount package, ensuring footprint compatibility with existing PCB designs without layout modifications.

Q: What moisture sensitivity level applies to these thermistors?

A: Both components carry MSL 1 (Unlimited) classification, indicating no moisture sensitivity restrictions during storage or handling. Standard component storage practices apply.