GMB20200 Trimmer Capacitor Equivalent & Substitute Parts

Part Overview

The GMB20200 is a 4–20pF trimmer capacitor rated at 175V with top adjustment and through-hole mounting, manufactured by Sprague-Goodman. This component is classified as obsolete, making equivalent substitutes necessary for ongoing design support and procurement. The part features mica dielectric construction, general-purpose application suitability, and unlimited moisture sensitivity rating (MSL 1). Identification of compatible alternatives requires matching capacitance range, voltage rating, adjustment type, mounting configuration, and physical dimensions within acceptable engineering tolerances.

Substiute Parts

GMB20200

Sprague-GoodmanIn Stock: 803GMB20200 Datasheet

Current PartRFQ

BFC280800006

Vishay Beyschlag/Draloric/BC ComponentsIn Stock: 2794BFC280800006 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

The BFC280800006 (Vishay Beyschlag/Draloric/BC Components) qualifies as a functional substitute based on the following alignment criteria:

Capacitance Coverage: The BFC280800006 provides a 2.5–22pF range, which encompasses the GMB20200 requirement of 4–20pF. The overlap region (4–20pF) permits direct substitution within the original design specification.

Voltage Rating: The substitute is rated at 250V, exceeding the GMB20200 requirement of 175V. This provides additional safety margin and is acceptable for direct replacement.

Adjustment Mechanism: Both parts feature top adjustment, ensuring identical mechanical interface and assembly compatibility.

Mounting Configuration: Both components use through-hole mounting, maintaining PCB footprint and assembly process compatibility.

Operating Temperature: The GMB20200 operates from –35°C to +85°C; the BFC280800006 operates from –40°C to +70°C. The substitute provides lower temperature extension (–40°C vs. –35°C) but has a reduced upper limit (70°C vs. 85°C). Circuit thermal analysis is required to confirm suitability in applications approaching +85°C.

Physical Dimensions: The BFC280800006 is significantly smaller (0.299" diameter, 0.394" height) compared to the GMB20200 (0.531" × 0.375" × 0.720" height). This dimensional reduction permits installation in space-constrained layouts but requires PCB footprint redesign.

Dielectric Material Change: The substitute uses polypropylene (PP) dielectric instead of mica. This material substitution affects frequency stability, temperature coefficient, and Q factor characteristics. Circuit performance validation is required before production implementation.

Product Status: The BFC280800006 is active and RoHS3 compliant, providing long-term availability and regulatory alignment.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitution Path: The BFC280800006 is the designated equivalent for GMB20200 applications where the following conditions are met:

1. Capacitance Adjustment Range: The circuit design must accommodate the 2.5–22pF range of the substitute. If the original design requires fixed capacitance values outside this range, substitution is not applicable.

2. Temperature Operating Envelope: If the application operates continuously above 70°C, the reduced upper temperature limit of the BFC280800006 (70°C vs. 85°C) requires thermal analysis to confirm component reliability. Applications with peak temperatures below 70°C are unconditionally compatible.

3. Dielectric Performance: The change from mica to polypropylene dielectric introduces differences in frequency stability and temperature coefficient. Applications requiring high-frequency stability or precision tuning characteristics must validate performance through circuit testing or simulation before production release.

4. Physical Layout: The smaller footprint of the BFC280800006 permits installation in space-constrained designs. However, PCB artwork and assembly documentation must be updated to reflect the new component dimensions and pad configuration.

5. Regulatory Compliance: The BFC280800006 RoHS3 compliance status aligns with current environmental regulations. The GMB20200 status is not specified; substitution with the BFC280800006 ensures regulatory alignment for new designs and legacy product updates.

6. Procurement and Availability: The BFC280800006 is active with 2700 units in stock, providing immediate availability and long-term supply continuity compared to the obsolete GMB20200.

Frequently Asked Questions (FAQ)

Q1: Can the BFC280800006 be used as a direct drop-in replacement for the GMB20200?

A: Physical drop-in replacement is not possible due to dimensional differences. The BFC280800006 is significantly smaller (0.299" diameter vs. 0.531" × 0.375" rectangular footprint). PCB artwork modification and component repositioning are required. However, electrical functionality is compatible within the specified parameter ranges.

Q2: What is the impact of changing from mica to polypropylene dielectric?

A: Polypropylene dielectric exhibits different frequency stability and temperature coefficient characteristics compared to mica. The substitute is suitable for general-purpose trimmer applications. Applications requiring precision frequency tuning or high-Q performance must validate performance through circuit testing before production implementation.

Q3: Is the BFC280800006 suitable for applications operating at 85°C?

A: The BFC280800006 is rated to 70°C maximum operating temperature, which is 15°C below the GMB20200 specification of 85°C. Applications with continuous operation near or above 70°C require thermal analysis to confirm component reliability. Applications with peak temperatures below 70°C are unconditionally compatible.

Q4: Does the higher voltage rating (250V vs. 175V) of the BFC280800006 affect circuit performance?

A: No. A higher voltage rating provides additional safety margin and does not degrade circuit performance. The substitute is fully compatible with circuits designed for 175V operation.

Q5: Are there any regulatory or compliance differences between the two parts?

A: The BFC280800006 is RoHS3 compliant; the GMB20200 compliance status is not specified. For new designs and legacy product updates subject to environmental regulations, the BFC280800006 ensures regulatory alignment. Both parts have MSL 1 (unlimited moisture sensitivity), indicating identical handling requirements.

Q6: What documentation updates are required for substitution?

A: Bill of materials (BOM), schematic designators, PCB artwork, assembly drawings, and component procurement specifications must be updated to reflect the BFC280800006 part number, manufacturer, and physical dimensions. Circuit performance validation documentation should be retained for traceability.