Bourns 3318F-1-105 Trimmer Potentiometer Equivalent & Substitute Parts

Part Overview

The Bourns 3318F-1-105 is a 1 MOhm, 0.1W through-hole trimmer potentiometer with top adjustment, featuring carbon resistive material and PC pin termination. This component is classified as obsolete, making identification of suitable substitutes necessary for ongoing production and maintenance applications. The Trimpot® 3318 series open frame design provides compact form factor for applications requiring precision resistance adjustment in confined spaces.

Substiute Parts

3318F-1-105

Bourns Inc.In Stock: 7793318F-1-105 Datasheet

Current PartRFQ

3306F-1-105

Bourns Inc.In Stock: 39713306F-1-105 Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

The Bourns 3306F-1-105 qualifies as a direct substitute based on the following alignment of critical electrical and mechanical parameters:

Matching Parameters:

• Resistance value: 1 MOhms (identical)
• Adjustment type: Top Adjustment (identical)
• Mounting type: Through Hole (identical)
• Termination style: PC Pins (identical)
• Number of turns: 1 (identical)
• RoHS3 compliance (identical)
• MSL rating: 1 (identical)

Allowable Variations:

• Power rating: 0.2W (1/5W) versus 0.1W (1/10W) — higher power rating provides enhanced thermal margin
• Tolerance: ±25% versus ±30% — tighter tolerance improves precision
• Temperature coefficient: ±250ppm/°C versus ±1000ppm/°C — superior temperature stability
• Resistive material: Cermet versus Carbon — improved performance characteristics
• Physical size: 0.319" x 0.268" (8.10mm x 6.80mm) versus 0.264" x 0.252" (6.70mm x 6.40mm) — slightly larger footprint

Parameter Comparison

Engineering Selection Recommendations

The 3306F-1-105 serves as the primary substitute for the obsolete 3318F-1-105. Selection of this substitute is supported by:

Product Status: The 3306F-1-105 maintains active product status with current manufacturing availability, whereas the 3318F-1-105 is obsolete.

Regulatory Compliance: Both components maintain ROHS3 compliance and identical MSL ratings, ensuring compatibility with current manufacturing and storage requirements.

Electrical Performance: The 3306F-1-105 provides equivalent resistance and adjustment characteristics with improved tolerance and temperature stability. The higher power rating (0.2W versus 0.1W) offers additional thermal headroom without compromising circuit function.

Physical Integration: The slightly larger footprint of the 3306F-1-105 requires verification of available PCB space. Existing through-hole mounting patterns remain compatible due to identical PC pin termination and adjustment type.

Frequently Asked Questions (FAQ)

Q: Can the 3306F-1-105 directly replace the 3318F-1-105 in existing designs?

A: Yes, provided PCB layout accommodates the larger physical dimensions (0.319" x 0.268" versus 0.264" x 0.252"). All electrical parameters and termination styles are compatible.

Q: What is the significance of the resistive material change from Carbon to Cermet?

A: Cermet material provides superior temperature stability (±250ppm/°C versus ±1000ppm/°C) and tighter tolerance (±25% versus ±30%), resulting in improved long-term performance and reduced drift over operating temperature ranges.

Q: Does the higher power rating of the 3306F-1-105 affect circuit operation?

A: No. The 0.2W rating of the 3306F-1-105 is a superset of the 0.1W requirement. Higher power rating indicates greater thermal capacity and does not alter electrical behavior in circuits designed for the lower rating.

Q: Are there packaging differences between these components?

A: The 3318F-1-105 is listed with standard packaging, while the 3306F-1-105 is supplied in bulk packaging. Both maintain identical MSL ratings and handling requirements.

Q: What compliance certifications apply to both components?

A: Both components are ROHS3 compliant, REACH unaffected, and classified under ECCN EAR99 for export purposes. MSL rating of 1 indicates unlimited shelf life under standard storage conditions.