FPXLF143-20 Equivalent & Substitute Parts

Part Overview

The FPXLF143-20 is a 14.31818 MHz crystal oscillator manufactured by Fox Electronics, designed for surface mount applications requiring fundamental mode operation. This part is classified as obsolete, making equivalent substitute components necessary for ongoing production and maintenance applications. The 20pF load capacitance and 40 Ohm ESR specifications define the electrical operating parameters for direct substitution candidates.

Substiute Parts

FPXLF143-20

Fox ElectronicsIn Stock: 1064FPXLF143-20 Datasheet

Current PartRFQ

ECS-143-20-7SX-TR

ECS Inc.In Stock: 927ECS-143-20-7SX-TR Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the FPXLF143-20 is determined by the following critical electrical parameters: frequency (14.31818 MHz), load capacitance (20pF), frequency tolerance (±50ppm), and ESR (40 Ohms). The substitute part ECS-143-20-7SX-TR meets these core electrical requirements with compatible frequency stability and load capacitance specifications. Both parts operate in fundamental mode with surface mount packaging and identical physical dimensions, enabling direct board-level replacement.

Parameter Comparison

Engineering Selection Recommendations

The ECS-143-20-7SX-TR serves as a direct electrical substitute for the obsolete FPXLF143-20. Both components share identical frequency, load capacitance, and physical dimensions. The ECS part offers improved frequency tolerance (±30ppm versus ±50ppm) and frequency stability (±50ppm versus ±100ppm), providing enhanced performance characteristics. The substitute operates at a slightly higher ESR (50 Ohms versus 40 Ohms), which remains within acceptable operating parameters for most applications. The ECS-143-20-7SX-TR is currently in active production status, ensuring long-term availability and supply chain continuity. Both parts maintain identical moisture sensitivity levels and regulatory compliance (REACH Unaffected, EAR99 classification). The operating temperature range of the substitute (-10°C to 70°C) is narrower than the original part (-20°C to 70°C); applications requiring operation below -10°C require evaluation against specific system requirements.

Frequently Asked Questions (FAQ)

Q: Can the ECS-143-20-7SX-TR directly replace the FPXLF143-20 on existing PCBs?

A: Yes. Both parts have identical physical dimensions (12.50mm x 4.60mm x 3.70mm) and surface mount configuration. The package designations differ (4-SMD No Lead versus 4-SOJ 9.40mm pitch), but the footprint and mounting requirements are compatible for board-level substitution.

Q: What is the significance of the ESR difference (40 Ohms versus 50 Ohms)?

A: The substitute part has a 10 Ohm higher ESR. This difference is within acceptable tolerance for most crystal oscillator applications and does not prevent functional substitution. System-level performance validation is recommended for applications with strict ESR requirements.

Q: Does the improved frequency tolerance of the substitute part affect compatibility?

A: No. The ECS-143-20-7SX-TR provides tighter frequency tolerance (±30ppm) compared to the original specification (±50ppm). This represents improved performance and does not create compatibility issues.

Q: Are there temperature range limitations with the substitute part?

A: The ECS-143-20-7SX-TR operates from -10°C to 70°C, compared to the original -20°C to 70°C range. Applications requiring operation below -10°C must be evaluated against specific system temperature requirements.

Q: What is the regulatory and compliance status of the substitute part?

A: The ECS-143-20-7SX-TR maintains identical regulatory compliance with the original part: REACH Unaffected status, EAR99 ECCN classification, and unlimited moisture sensitivity level (MSL 1). Both parts are suitable for equivalent regulatory environments.

Q: Why is the original FPXLF143-20 classified as obsolete?

A: Obsolete status indicates the part is no longer manufactured by Fox Electronics. The ECS-143-20-7SX-TR is an active production alternative that provides equivalent electrical and mechanical functionality for ongoing applications.