Equivalent & Substitute Parts for 103GG1K

Part Overview

The 103GG1K is an NTC thermistor manufactured by Littelfuse Inc., rated at 10kΩ resistance at 25°C with a B0/50 value of 3575K. This component is packaged in DO-204AH (DO-35) axial configuration for through-hole mounting applications. The part is currently listed as obsolete, making identification of suitable substitutes necessary for ongoing system support and component procurement.

Substiute Parts

103GG1K

Littelfuse Inc.In Stock: 1065103GG1K Datasheet

Current PartRFQ

103FG1K

LittelfuseIn Stock: 1346103FG1K Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The 103FG1K qualifies as a direct substitute for the 103GG1K based on the following matching parameters:

• Resistance value: 10kΩ at 25°C
• Resistance tolerance: ±10%
• Operating temperature maximum: 300°C
• Lead wire length: 1.00" (25.40mm)
• Mounting type: Through Hole
• Package configuration: DO-204AH, DO-35, Axial
• RoHS3 compliance and REACH unaffected status

The B0/50 value differs (3419K vs. 3575K), representing a variance in the thermal response characteristic. Both values fall within the operational envelope for NTC thermistor applications requiring 10kΩ base resistance.

Parameter Comparison

Engineering Selection Recommendations

The 103FG1K is an active product from Littelfuse with identical mechanical and electrical specifications to the 103GG1K, with the exception of the B0/50 thermal coefficient value. Both components maintain ROHS3 compliance and REACH unaffected status, ensuring regulatory alignment for new designs and legacy system support.

The transition from the obsolete 103GG1K to the active 103FG1K is supported by matching package geometry, lead configuration, and core resistance parameters. The B0/50 variance (3419K vs. 3575K) represents a 4.2% difference in thermal response and should be evaluated within the context of the specific temperature measurement or compensation application.

Frequently Asked Questions (FAQ)

Q: Can the 103FG1K directly replace the 103GG1K in existing assemblies?

A: Yes. Both components share identical mechanical dimensions (DO-35 axial package, 1.00" lead length), mounting type (through-hole), and core electrical specifications (10kΩ ±10% at 25°C, 300°C operating temperature). The B0/50 thermal coefficient difference requires application-level verification if precise temperature compensation curves are critical.

Q: What is the significance of the B0/50 value difference?

A: The B0/50 value defines the thermistor's thermal response between 0°C and 50°C. The 103FG1K (3419K) exhibits a slightly different temperature-resistance curve compared to the 103GG1K (3575K). Applications requiring specific temperature measurement accuracy should validate this parameter against system requirements.

Q: Why is the 103GG1K listed as obsolete?

A: Littelfuse has transitioned this part number to end-of-life status. The 103FG1K remains in active production and provides equivalent functionality for new designs and component replenishment.

Q: Are there any compliance differences between these parts?

A: No. Both components are ROHS3 compliant and REACH unaffected, maintaining identical regulatory status for procurement and deployment.

Q: What packaging options are available for the 103FG1K?

A: The 103FG1K is supplied in bulk packaging, whereas the 103GG1K packaging type was not specified in available data.