EJ5 Trimmer Capacitor Equivalent & Substitute Parts

Part Overview

The EJ5 is a 0.8–5pF trimmer capacitor rated for 250V operation in a side-adjustment surface mount configuration, manufactured by Knowles Voltronics. This component is classified as obsolete, making identification of functionally equivalent alternatives necessary for ongoing design support and procurement planning. The EJ5 serves general-purpose trimming applications requiring stable capacitance adjustment across the specified range.

Substiute Parts

EJ5

Knowles VoltronicsIn Stock: 955EJ5 Datasheet

Current PartRFQ

27271SL

Knowles Johanson ManufacturingIn Stock: 178227271SL Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

The 27271SL (Knowles Johanson Manufacturing, Giga-Trim® series) qualifies as a functional substitute based on the following alignment of critical parameters:

• Adjustment Type: Both parts feature side adjustment, ensuring mechanical compatibility with existing trimmer designs.
• Mounting Type: Both are surface mount components, maintaining PCB integration compatibility.
• Operating Temperature Range: Both support –65°C to 125°C operation, ensuring thermal performance equivalence.
• Moisture Sensitivity Level: Both are MSL 1 (Unlimited), indicating identical moisture handling requirements.
• Capacitance Range Overlap: The 27271SL range (0.6–4.5pF) overlaps substantially with the EJ5 range (0.8–5pF), covering the majority of typical application requirements within 0.8–4.5pF.
• Voltage Rating: The 27271SL is rated for 500V, exceeding the EJ5's 250V requirement, providing enhanced voltage margin.

The 27271SL represents an active product with current manufacturing support, addressing the obsolescence status of the EJ5.

Parameter Comparison

Engineering Selection Recommendations

The 27271SL is suitable for applications currently using the EJ5 within the overlapping capacitance range of 0.8–4.5pF. The substitute offers the following advantages:

• Active Product Status: The 27271SL is in active production, ensuring long-term availability and supply chain stability compared to the obsolete EJ5.
• Enhanced Voltage Rating: The 500V rating provides additional design margin for applications operating at or near the EJ5's 250V limit.
• RoHS3 Compliance: The 27271SL meets ROHS3 requirements, supporting modern procurement and environmental compliance standards.
• Reduced Physical Footprint: The smaller 0.140" diameter (4.66mm) enables more compact PCB layouts compared to the EJ5's 0.300" diameter.

Applications requiring capacitance values above 4.5pF (up to the EJ5's maximum of 5pF) will require alternative component selection outside this substitute relationship.

Frequently Asked Questions (FAQ)

Q: Can the 27271SL directly replace the EJ5 in all applications?

A: The 27271SL is compatible for applications using capacitance values between 0.8pF and 4.5pF. Applications requiring the full 0.8–5pF range of the EJ5 will need alternative solutions for settings above 4.5pF.

Q: What are the physical compatibility considerations?

A: Both parts use side-adjustment surface mount packaging. The 27271SL has a smaller diameter (0.140" vs. 0.300"), which may require PCB layout verification to ensure adequate clearance and adjustment access. Height specifications differ; the EJ5 specifies 0.500" maximum seated height, while the 27271SL height is not provided.

Q: How do the dielectric materials differ?

A: The EJ5 uses polytetrafluoroethylene (PTFE), while the 27271SL uses sapphire. Both materials are suitable for general-purpose trimmer applications across the specified temperature range.

Q: Is the 27271SL suitable for high-frequency applications?

A: The 27271SL is specified at 250MHz with a Q of 3000, compared to the EJ5 at 100MHz with a Q of 5000. Application suitability depends on the specific frequency requirements of the circuit.

Q: What compliance advantages does the 27271SL offer?

A: The 27271SL is ROHS3 compliant and manufactured by an active product line, supporting modern procurement standards and environmental regulations. The EJ5, being obsolete, may present compliance and sourcing challenges.