KX222J2 Equivalent & Substitute Parts

Part Overview

The KX222J2 is an NTC thermistor manufactured by Littelfuse Inc., designed as a temperature sensor with a nominal resistance of 2.252kΩ at 25°C and a B value of 3892K. This component features an epoxy bead package with free-hanging mounting configuration and operates up to 120°C with a maximum power dissipation of 30mW.

The KX222J2 is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity and ensure component availability for applications requiring NTC thermistor functionality with matching electrical and thermal characteristics.

Substiute Parts

KX222J2

Littelfuse Inc.In Stock: 814KX222J2 Datasheet

Current PartRFQ

2152723205

MolexIn Stock: 23862152723205 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for NTC thermistor components is determined by the following critical parameters:

• Resistance value at 25°C (must match within tolerance specification)
• B value coefficient (must match to ensure equivalent thermal response)
• Operating temperature range (substitute must meet or exceed application requirements)
• Package configuration (bead type and lead wire dimensions)
• Compliance certifications (RoHS and REACH status)

The substitute part 2152723205 (Molex) satisfies these criteria through matching resistance (2.252kΩ ±1%), identical B value (3892K), compatible operating temperature range (-40°C to 135°C, which exceeds the original 120°C maximum), and equivalent epoxy bead package construction. Both components maintain ROHS3 compliance and share the same HTSUS classification.

Parameter Comparison

Engineering Selection Recommendations

The 2152723205 (Molex) serves as a direct functional substitute for the obsolete KX222J2. Both components share identical resistance and B value specifications, ensuring equivalent thermal response characteristics in temperature sensing applications.

The substitute part maintains active product status, providing assured long-term availability and supply chain continuity. Both components are ROHS3 compliant, satisfying environmental and regulatory requirements for equivalent applications.

The operating temperature range of the substitute (-40°C to 135°C) encompasses the original specification (120°C maximum), confirming thermal compatibility for existing designs. Lead wire length differs by 5mm (33mm versus 38mm), which may require mechanical accommodation in circuit board layouts or sensor mounting configurations.

Frequently Asked Questions (FAQ)

Q: Can the 2152723205 directly replace the KX222J2 in existing designs?

A: The 2152723205 provides electrical equivalence through matching resistance (2.252kΩ) and B value (3892K) specifications. Physical accommodation may be required due to a 5mm difference in lead wire length (33mm versus 38mm). Mounting configuration differs (through-hole versus free-hanging), necessitating mechanical design review.

Q: What determines if an NTC thermistor can substitute for the KX222J2?

A: Substitution requires matching resistance value at 25°C, identical B value coefficient, operating temperature range that meets or exceeds application requirements, and compatible package configuration. Compliance certifications must align with application standards.

Q: Are there compliance differences between these components?

A: Both the KX222J2 and 2152723205 are ROHS3 compliant. The substitute is REACH Affected, while the original is REACH Unaffected. Application requirements should determine if this distinction impacts component selection.

Q: How does the lead wire length difference affect substitution?

A: The 5mm difference in lead wire length (KX222J2 at 38mm versus 2152723205 at 33mm) may impact sensor insertion depth, thermal coupling characteristics, or circuit board layout. Physical integration review is necessary for applications with specific mounting constraints.

Q: What is the significance of the different mounting types?

A: The KX222J2 uses free-hanging configuration, while the 2152723205 is designed for through-hole mounting. This difference requires mechanical redesign or adapter consideration depending on the application's sensor mounting methodology.