MC18FD391F-F Equivalent & Substitute Parts

Part Overview

The MC18FD391F-F is a 390 pF mica capacitor manufactured by Cornell Dubilier Electronics (CDE), rated for 500 V operation in a 1812 (4532 Metric) surface mount package. This component is classified as an active product with ROHS3 compliance and unlimited moisture sensitivity rating (MSL 1). Mica capacitors in this specification are utilized in RF applications requiring high Q factor and low loss characteristics across the operating temperature range of -55°C to 125°C. Alternative models may be required when tolerance specifications differ from the original design requirement or when inventory constraints necessitate substitution with equivalent electrical performance.

Substiute Parts

MC18FD391F-F

Cornell Dubilier Electronics (CDE)In Stock: 827MC18FD391F-F Datasheet

Current PartRFQ

MC18FD391J-F

Cornell Dubilier Electronics (CDE)In Stock: 1172MC18FD391J-F Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the MC18FD391F-F is permissible with the MC18FD391J-F based on the following criteria:

Matching Parameters (Substitution Basis):

• Capacitance value: 390 pF (identical)
• Voltage rating: 500 V (identical)
• Dielectric material: Mica (identical)
• Operating temperature range: -55°C to 125°C (identical)
• Mounting type: Surface Mount (identical)
• Package / Case: 1812 (4532 Metric) (identical)
• Physical dimensions: 4.50mm × 3.20mm × 2.00mm (identical)
• RoHS compliance: ROHS3 Compliant (identical)
• MSL rating: 1 (Unlimited) (identical)

Differing Parameter:

• Tolerance: MC18FD391F-F specifies ±1%, while MC18FD391J-F specifies ±5%

The MC18FD391J-F functions as an electrical and mechanical equivalent with relaxed tolerance specification. Substitution is valid only when circuit design permits the wider ±5% tolerance band.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection (MC18FD391F-F): Select the MC18FD391F-F when circuit design specifications require ±1% capacitance tolerance. This part maintains active product status with full ROHS3 compliance and unlimited moisture sensitivity rating, ensuring compatibility with standard surface mount assembly processes.

Substitute Selection (MC18FD391J-F): The MC18FD391J-F is electrically and mechanically equivalent and may be selected when circuit design tolerates ±5% capacitance variation. Both parts share identical voltage rating, temperature operating range, package dimensions, and compliance certifications. Selection of the substitute part is valid only when tolerance relaxation does not compromise circuit performance or specification requirements.

Compliance Considerations: Both parts maintain ROHS3 compliance and REACH unaffected status, suitable for applications subject to environmental regulations. MSL 1 rating (unlimited moisture sensitivity) permits standard handling and storage without desiccant requirements.

Frequently Asked Questions (FAQ)

Q: Can MC18FD391J-F replace MC18FD391F-F in all applications?

A: No. The MC18FD391J-F has ±5% tolerance versus ±1% for the MC18FD391F-F. Substitution is valid only when the circuit design specification permits the wider tolerance band. Review schematic tolerance requirements before substitution.

Q: Are the physical dimensions identical between both parts?

A: Yes. Both parts use the 1812 (4532 Metric) package with identical dimensions of 4.50mm length × 3.20mm width × 2.00mm maximum seated height. PCB footprints and assembly processes are interchangeable.

Q: Do both parts have the same voltage rating?

A: Yes. Both MC18FD391F-F and MC18FD391J-F are rated for 500 V operation. Voltage derating curves and maximum operating voltage are identical.

Q: What is the operating temperature range for these parts?

A: Both parts operate across -55°C to 125°C. Temperature coefficient and performance characteristics remain consistent across this range for both variants.

Q: Are there any compliance differences between the two parts?

A: No. Both parts are ROHS3 compliant, REACH unaffected, and carry MSL 1 (unlimited) moisture sensitivity rating. Regulatory and environmental compliance is identical.

Q: Which part should be used for RF applications?

A: Both parts are specified for RF applications with high Q factor and low loss characteristics. Selection between them depends solely on tolerance requirements, not RF performance.

Q: What is the difference in capacitance tolerance between these parts?

A: MC18FD391F-F has ±1% tolerance, meaning capacitance ranges from 386.1 pF to 393.9 pF. MC18FD391J-F has ±5% tolerance, with capacitance ranging from 370.5 pF to 409.5 pF. The ±1% part provides tighter capacitance control.