GMB20000 Equivalent & Substitute Parts Reference

Part Overview

The GMB20000 is a 2.5–7pF 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 production and maintenance applications. Trimmer capacitors in this capacitance range are used for circuit tuning and frequency adjustment in RF and general-purpose electronic applications. The discontinuation of the GMB20000 requires identification of functionally compatible alternatives that maintain electrical performance within system design tolerances.

Substiute Parts

GMB20000

Sprague-GoodmanIn Stock: 898GMB20000 Datasheet

Current PartRFQ

BFC280800006

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

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the GMB20000 is based on the following electrical and mechanical compatibility criteria:

Capacitance Range: The substitute BFC280800006 provides a 2.5–22pF range, which encompasses the 2.5–7pF requirement of the GMB20000. This extended range allows the substitute to function across the full tuning spectrum of the original component.

Voltage Rating: The BFC280800006 is rated at 250V, exceeding the 175V requirement of the GMB20000. This higher rating ensures adequate safety margin and reliability in the application.

Adjustment Type: Both components feature top adjustment, maintaining identical mechanical interface and operator accessibility.

Mounting Configuration: Both components are through-hole mounted, preserving PCB assembly compatibility without requiring layout modifications.

Operating Temperature: The BFC280800006 operates from –40°C to +70°C. The lower limit (–40°C) exceeds the GMB20000 specification (–35°C), providing enhanced cold-temperature performance. The upper limit (+70°C) is within the GMB20000 range (+85°C), representing a 15°C reduction in maximum operating temperature. This difference must be evaluated against specific application thermal requirements.

Dielectric Material: The GMB20000 uses mica dielectric, while the BFC280800006 uses polypropylene (PP). Both materials are suitable for general-purpose trimmer applications and provide stable capacitance characteristics across the operating temperature range.

Physical Size: The BFC280800006 has a smaller footprint (0.299" diameter × 0.394" height) compared to the GMB20000 (0.531" × 0.375" × 0.720" height), allowing installation in space-constrained applications.

Product Status & Compliance: The BFC280800006 is active and RoHS3 compliant, ensuring long-term availability and regulatory compliance for new designs.

Parameter Comparison

Engineering Selection Recommendations

Primary Substitute: BFC280800006 is the designated equivalent for GMB20000 applications.

Justification:

1. Electrical Compatibility: The BFC280800006 meets all critical electrical parameters. Its 2.5–22pF capacitance range fully covers the 2.5–7pF requirement, and its 250V rating provides a 75V safety margin above the 175V specification.

2. Mechanical Compatibility: Top adjustment and through-hole mounting are identical, eliminating the need for PCB redesign or assembly procedure changes.

3. Product Status: The BFC280800006 is active and in production, ensuring reliable long-term supply and availability for both new production and field service applications.

4. Regulatory Compliance: RoHS3 compliance of the BFC280800006 satisfies current environmental and regulatory requirements for electronic components in most jurisdictions.

5. Temperature Consideration: The maximum operating temperature of the BFC280800006 (+70°C) is 15°C lower than the GMB20000 (+85°C). Applications operating continuously above +70°C require thermal analysis to confirm the substitute remains within safe operating limits.

6. Physical Footprint: The smaller dimensions of the BFC280800006 provide layout flexibility. Verify that the reduced size does not create mechanical clearance issues with adjacent components or enclosure constraints.

Frequently Asked Questions (FAQ)

Q1: Can the BFC280800006 directly replace the GMB20000 without circuit modification?

A: Yes, for applications operating within the BFC280800006 temperature range (–40°C to +70°C) and voltage requirements (≤250V). The identical adjustment type and mounting method eliminate mechanical redesign. However, verify that the application's maximum operating temperature does not exceed +70°C.

Q2: What is the significance of the capacitance range difference (2.5–7pF vs. 2.5–22pF)?

A: The BFC280800006 provides a wider tuning range. If the original design requires adjustment only within 2.5–7pF, the substitute will function identically within that range. The extended upper limit (22pF) does not affect performance in the original application but provides additional tuning capability if future circuit modifications are needed.

Q3: Does the dielectric material change from mica to polypropylene affect circuit performance?

A: Both mica and polypropylene are established dielectric materials for trimmer capacitors. The polypropylene dielectric in the BFC280800006 provides stable capacitance across the operating temperature range and is suitable for general-purpose tuning applications. Specific performance differences depend on the application's frequency and stability requirements; consult application-specific technical data if high-Q or precision frequency stability is critical.

Q4: Why is the maximum operating temperature of the substitute lower (+70°C vs. +85°C)?

A: Different manufacturers design components for different thermal specifications based on dielectric material properties and construction. The BFC280800006's +70°C maximum is typical for polypropylene-based trimmers. Applications with continuous operation above +70°C require thermal analysis to confirm the substitute remains within safe operating limits and maintains capacitance stability.

Q5: Are there any PCB layout considerations when switching from GMB20000 to BFC280800006?

A: The BFC280800006 has a smaller footprint (0.299" diameter vs. 0.531" length). Verify that the reduced size does not create mechanical clearance issues with adjacent components. The through-hole mounting pattern should be confirmed with the substitute's datasheet to ensure pad compatibility.

Q6: Is the BFC280800006 available in the same packaging as the GMB20000?

A: The GMB20000 is listed as obsolete with no current packaging specification. The BFC280800006 is available in bulk packaging and is in active production, ensuring consistent availability for both prototype and production quantities.

Q7: What compliance certifications apply to the BFC280800006?

A: The BFC280800006 is RoHS3 compliant and carries ECCN EAR99 classification, meeting current environmental and export control requirements. Moisture Sensitivity Level is 1 (Unlimited), indicating no special moisture handling is required during storage or assembly.