Equivalent & Substitute Parts for PR503J2

Part Overview

The PR503J2 is an NTC thermistor with 50kΩ resistance at 25°C, manufactured by Littelfuse Inc. in a bead configuration with epoxy encapsulation. This component is classified as obsolete, making identification of suitable substitutes essential for ongoing system support and component procurement.

The PR503J2 operates across a temperature range of -55°C to 80°C with a maximum power dissipation of 30 mW. Its bead form factor and free-hanging mounting type define its mechanical integration requirements.

Substiute Parts

PR503J2

Littelfuse Inc.In Stock: 975PR503J2 Datasheet

Current PartRFQ

PS503J2

Littelfuse Inc.In Stock: 1315PS503J2 Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the PR503J2 is determined by the following critical parameters:

• Resistance value at 25°C: 50kΩ (exact match required)
• B0/50 thermal coefficient: 3892K (exact match required)
• Maximum power dissipation: 30 mW (minimum requirement)
• Package configuration: Bead, Epoxy (mechanical compatibility)
• Lead wire length: 1.50" (38.00mm) (form factor compatibility)
• Mounting type: Free Hanging (installation compatibility)

The PS503J2 meets all substitution criteria. While it features an extended operating temperature range (-80°C to 150°C versus -55°C to 80°C) and different resistance tolerance specification, these represent functional improvements that maintain backward compatibility with PR503J2 applications.

Parameter Comparison

Engineering Selection Recommendations

The PS503J2 is the direct substitute for the PR503J2. Both components are manufactured by Littelfuse Inc. and share identical electrical specifications: 50kΩ resistance at 25°C and 3892K B-value. Both maintain ROHS3 compliance and identical mechanical form factors.

The PS503J2 is currently in active production status, whereas the PR503J2 is obsolete. The PS503J2 provides an extended operating temperature range (-80°C to 150°C) compared to the PR503J2 (-55°C to 80°C), which represents a functional enhancement without introducing compatibility constraints for existing applications.

Frequently Asked Questions (FAQ)

Q: Can PS503J2 directly replace PR503J2 in existing designs?

A: Yes. Both components share identical resistance values (50kΩ), B-values (3892K), power ratings (30 mW), lead wire lengths (1.50"), and package configurations (Bead, Epoxy). The PS503J2 operates across a wider temperature range, making it suitable for all PR503J2 applications.

Q: What is the significance of the B0/50 value in thermistor selection?

A: The B0/50 value (3892K) defines the thermal response characteristic of the NTC thermistor. Substitutes must match this value to maintain equivalent temperature sensing behavior across the operating range.

Q: Are there packaging differences between PR503J2 and PS503J2?

A: Both components use identical Bead, Epoxy packaging with 1.50" lead wire length and free-hanging mounting configuration. The primary difference is that PS503J2 is supplied in bulk packaging, whereas PR503J2 was supplied in standard packaging.

Q: Why is PR503J2 marked as obsolete?

A: PR503J2 has been discontinued by the manufacturer. PS503J2 represents the active production equivalent and should be used for all new procurement and design activities.

Q: Do both parts meet the same compliance standards?

A: Yes. Both PR503J2 and PS503J2 are ROHS3 compliant and REACH unaffected, meeting equivalent regulatory requirements for electronic component deployment.