B57504K103A3 NTC Thermistor 10kΩ Cylindrical Probe - Equivalent & Substitute Parts

Part Overview

The B57504K103A3 is an NTC thermistor temperature sensor manufactured by EPCOS - TDK Electronics, featuring a 10kΩ resistance at 25°C in a cylindrical probe configuration with copper construction. This component is classified as obsolete, making identification of suitable substitute parts essential for ongoing system support and new design implementations. The part operates across a temperature range of -20°C to 85°C with a maximum power dissipation of 60mW, designed for free-hanging mounting applications.

Substiute Parts

B57504K103A3

EPCOS - TDK ElectronicsIn Stock: 1026B57504K103A3 Datasheet

Current PartRFQ

B57500K0103A001

EPCOS - TDK ElectronicsIn Stock: 899B57500K0103A001 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the B57504K103A3 is determined by the following criteria:

Electrical Compatibility Requirements:

• Resistance value must be 10kΩ at 25°C
• Resistance tolerance must be ±2% or tighter
• B value tolerance must be ±1% or tighter to maintain thermal response characteristics
• Maximum power dissipation must be ≥60mW

Thermal Compatibility Requirements:

• Operating temperature range must encompass or exceed -20°C to 85°C

Mechanical & Physical Compatibility:

• Package configuration must be cylindrical probe with copper construction
• Mounting type must be free-hanging
• Lead wire length must be compatible with circuit board layout

Regulatory & Compliance Requirements:

• RoHS3 compliance mandatory
• REACH compliance status must match or exceed current part

The B57500K0103A001 qualifies as a direct substitute based on these parameters, with the additional benefit of active product status and improved B value tolerance.

Parameter Comparison

Engineering Selection Recommendations

The B57500K0103A001 is the qualified substitute for the obsolete B57504K103A3 based on the following engineering factors:

Product Status Advantage: The substitute part maintains active manufacturing status with EPCOS - TDK Electronics, ensuring long-term availability and supply chain continuity compared to the obsolete main part.

Electrical Performance: Both parts share identical resistance values (10kΩ) and tolerance specifications (±2%), with the substitute offering improved B value tolerance (±0.5% versus ±1%), resulting in enhanced temperature coefficient stability and reduced calibration drift over the component lifetime.

Thermal Operating Range: The substitute extends the upper operating temperature limit from 85°C to 100°C. Applications requiring operation below 0°C must verify that the substitute's 0°C lower limit is acceptable, as the main part supports -20°C operation.

Mechanical Integration: Both components utilize identical cylindrical probe copper construction and free-hanging mounting. The substitute features longer lead wires (470mm versus 367mm), requiring verification that circuit board layout and component placement accommodate the increased lead length without introducing mechanical stress or routing conflicts.

Regulatory Compliance: Both parts maintain ROHS3 compliance and REACH compliance status, satisfying current environmental and regulatory requirements for component selection.

Frequently Asked Questions (FAQ)

Q: Can the B57500K0103A001 be used as a direct replacement for the B57504K103A3 in all applications?

A: The B57500K0103A001 qualifies as a direct electrical and mechanical substitute for applications operating within the 0°C to 85°C temperature range. Applications requiring operation below 0°C must evaluate whether the substitute's 0°C lower limit is acceptable for the specific thermal environment. Lead wire length differences (470mm versus 367mm) must be verified against circuit board layout constraints.

Q: What is the significance of the B value tolerance difference between these parts?

A: The main part specifies ±1% B value tolerance, while the substitute offers ±0.5% tolerance. B value tolerance directly affects the thermistor's temperature coefficient stability. The tighter tolerance of the substitute results in more consistent thermal response characteristics across the operating temperature range, potentially reducing calibration requirements and improving long-term measurement accuracy.

Q: Are there any compliance or certification differences between these parts?

A: Both parts maintain identical RoHS3 and REACH compliance status. No compliance or certification differences exist between the main part and substitute.

Q: How should the longer lead wire length of the substitute be evaluated?

A: The substitute features 103mm longer lead wires (470mm versus 367mm). Circuit board layout must be reviewed to confirm that the extended lead length does not create mechanical stress, introduce routing conflicts, or compromise thermal isolation requirements. If the longer leads are incompatible with the existing design, lead trimming may be performed during assembly, provided thermal and electrical performance specifications are maintained.

Q: Why is the main part classified as obsolete?

A: The B57504K103A3 is classified as obsolete by the manufacturer, indicating discontinued production. The B57500K0103A001 represents the active replacement part from EPCOS - TDK Electronics, ensuring continued availability and manufacturing support for new designs and system maintenance.