GSX358 Trimmer Capacitor Equivalent & Substitute Parts

Part Overview

The GSX358 is a surface mount trimmer capacitor manufactured by Sprague-Goodman, part of the FILMTRIM® series. This component is a 0.6–9pF capacitor rated for 100V operation with top-side adjustment capability and polytetrafluoroethylene (PTFE) dielectric material. The GSX358 is classified as obsolete, making identification of suitable substitute components essential for ongoing design support and production continuity. Equivalent parts must satisfy the functional requirements of trimmer capacitance adjustment within specified voltage and temperature operating ranges while maintaining compatible surface mount packaging.

Substiute Parts

GSX358

Sprague-GoodmanIn Stock: 701GSX358 Datasheet

Current PartRFQ

JZ100

Knowles VoltronicsIn Stock: 50553JZ100 Datasheet

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Key Parameters

Substitute Part Grouping Explanation

Substitution of the obsolete GSX358 is evaluated based on functional equivalence within the following critical parameters:

Capacitance Range Compatibility: The substitute must provide a capacitance adjustment range that encompasses or closely overlaps the 0.6–9pF range of the GSX358. The JZ100 provides a 2–10pF range, which covers the upper portion of the GSX358 operating window and extends the upper limit by 1pF.

Voltage Rating: The substitute must meet or exceed the 100V rating of the GSX358. The JZ100 is rated for 125V, providing adequate voltage margin.

Adjustment Type: Both components feature top-side adjustment, ensuring mechanical compatibility in circuit board layout and tuning procedures.

Mounting Configuration: Both components are surface mount devices with compatible footprint categories, allowing direct substitution in PCB assembly processes.

Operating Temperature Range: The substitute must support the thermal operating window. The GSX358 operates from −25°C to +85°C; the JZ100 extends this to −40°C to +85°C, providing enhanced low-temperature performance.

Moisture Sensitivity: Both components carry MSL 1 classification, indicating unlimited shelf life and identical moisture handling requirements.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: The JZ100 (Knowles Voltronics) is the designated substitute for the obsolete GSX358. Selection is based on the following engineering criteria:

Product Status and Availability: The GSX358 is obsolete with no ongoing manufacturing. The JZ100 is in active production status, ensuring long-term component availability and supply chain continuity.

Regulatory Compliance: The JZ100 carries RoHS Compliant certification, meeting current environmental and regulatory standards. The GSX358 compliance status is not specified in available documentation.

Functional Equivalence: Both components provide top-adjustment trimmer capacitor functionality in surface mount packages. The JZ100 capacitance range (2–10pF) overlaps substantially with the GSX358 range (0.6–9pF), with the exception of the 0.6–2pF lower adjustment window.

Voltage and Temperature Performance: The JZ100 exceeds the GSX358 voltage rating (125V vs. 100V) and extends the low-temperature operating limit (−40°C vs. −25°C), providing enhanced performance margins.

Physical Footprint Consideration: The JZ100 is significantly smaller (4.50mm × 3.20mm vs. 7.20mm × 5.40mm) and lower profile (1.45mm vs. 2.20mm). PCB layout modification is required; however, the reduced footprint may provide design benefits in space-constrained applications.

Dielectric Material Difference: The GSX358 uses PTFE dielectric; the JZ100 uses ceramic dielectric. This material difference affects frequency stability characteristics and Q factor performance. Circuit-level validation is required to confirm performance equivalence in the specific application frequency range.

Frequently Asked Questions (FAQ)

Q: Can the JZ100 directly replace the GSX358 without PCB modification?

A: No. While both components are surface mount trimmer capacitors with top adjustment, the JZ100 has a significantly smaller footprint (4.50mm × 3.20mm vs. 7.20mm × 5.40mm). PCB layout modification is necessary to accommodate the different pad pattern and component placement.

Q: What is the impact of the capacitance range difference (0.6–9pF vs. 2–10pF)?

A: The JZ100 cannot achieve capacitance values below 2pF. If the circuit design requires tuning in the 0.6–2pF range, the JZ100 is not suitable. For applications requiring adjustment only within the 2–9pF window, the JZ100 is fully compatible.

Q: Does the dielectric material change from PTFE to ceramic affect circuit performance?

A: Dielectric material affects frequency stability, temperature coefficient, and Q factor. The GSX358 PTFE dielectric and JZ100 ceramic dielectric have different electrical characteristics. Circuit-level testing is required to validate performance equivalence at the operating frequency of the specific application.

Q: Are the moisture sensitivity and storage requirements identical?

A: Yes. Both the GSX358 and JZ100 carry MSL 1 (Unlimited) classification, indicating identical moisture sensitivity levels and unlimited shelf life under standard storage conditions.

Q: What is the voltage margin provided by the JZ100?

A: The JZ100 is rated for 125V compared to the GSX358 rating of 100V, providing a 25V safety margin. This allows operation in higher voltage applications without derating.

Q: Is the JZ100 RoHS compliant?

A: Yes. The JZ100 is RoHS Compliant. The GSX358 compliance status is not documented in available specifications.

Q: Can the JZ100 operate at lower temperatures than the GSX358?

A: Yes. The JZ100 operating temperature range is −40°C to +85°C, compared to the GSX358 range of −25°C to +85°C. The JZ100 provides 15°C additional low-temperature capability.