CTX25-1P-R Equivalent & Substitute Parts

Part Overview

The CTX25-1P-R is an unshielded 2-coil inductor array manufactured by Eaton - Electronics Division, part of the Econo-Pac™ series. This surface mount component provides dual inductance configurations: 25.4 µH in parallel connection and 101.6 µH in series connection. The part is classified as Active product status with full RoHS3 compliance and unlimited moisture sensitivity rating (MSL 1).

Substitute parts are identified when equivalent electrical performance and mechanical compatibility can be maintained within the specified parameter tolerances. The primary substitute identified is the SLF10145T-220M1R9-PF from TDK Corporation, which operates under different core construction and shielding characteristics but maintains functional equivalence for specific application requirements.

Substiute Parts

CTX25-1P-R

Eaton - Electronics DivisionIn Stock: 833CTX25-1P-R Datasheet

Current PartRFQ

SLF10145T-220M1R9-PF

TDK CorporationIn Stock: 55399SLF10145T-220M1R9-PF Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the CTX25-1P-R is determined by the following critical parameters:

Inductance Value Compatibility: The substitute part must operate within the ±20% tolerance band of the required inductance specification. For parallel configuration applications requiring 25.4 µH, acceptable inductance range is 20.32 µH to 30.48 µH. For series configuration applications requiring 101.6 µH, acceptable range is 81.28 µH to 121.92 µH.

Current Rating Sufficiency: The substitute must support the required current level without saturation. Parallel configuration requires minimum 960 mA rating; series configuration requires minimum 480 mA rating.

DC Resistance (DCR) Characteristics: Maximum allowable DCR values are 177 mOhm for parallel and 708 mOhm for series configurations. Lower DCR values reduce power dissipation and heat generation.

Mounting and Package Compatibility: Both parts must be surface mount technology suitable for automated assembly on standard PCB equipment.

Environmental and Compliance Requirements: Operating temperature range must encompass the application environment. RoHS3 compliance and MSL 1 rating are mandatory for specified applications.

Shielding Consideration: While the CTX25-1P-R is unshielded, shielded substitutes may be used in applications where EMI mitigation is beneficial, provided all other electrical parameters remain within specification.

Parameter Comparison

Engineering Selection Recommendations

For Active Product Line Applications: The CTX25-1P-R is the primary selection for new designs. As an Active product with full manufacturing support, it provides long-term availability and supply chain stability. This part is recommended when design flexibility permits and when the unshielded configuration is acceptable for the application environment.

For Substitute Selection - SLF10145T-220M1R9-PF: The SLF10145T-220M1R9-PF from TDK Corporation is suitable as a substitute when the CTX25-1P-R is unavailable or when specific performance advantages are required. This substitution is valid under the following conditions:

The application requires 22 µH inductance, which falls within the ±20% tolerance band of the CTX25-1P-R parallel configuration (25.4 µH).

The application can accommodate shielded construction, which provides EMI rejection benefits in noise-sensitive circuits.

The application environment does not exceed 105°C, allowing full utilization of the extended temperature range.

The smaller footprint (10.10mm x 10.10mm versus 11.43mm x 11.43mm) is compatible with PCB layout constraints.

The "Not For New Designs" status of the SLF10145T-220M1R9-PF indicates this part is suitable for replacement, legacy support, or applications where supply has been previously established. For new product development, the CTX25-1P-R is the preferred selection.

Compliance Verification: Both parts maintain ROHS3 compliance and MSL 1 rating, satisfying environmental and handling requirements for standard manufacturing processes. No additional qualification is required from a compliance perspective.

Frequently Asked Questions (FAQ)

Q: Can the SLF10145T-220M1R9-PF directly replace the CTX25-1P-R in all applications?

A: Direct replacement is valid only when the application requirements align with the substitute's specifications. The 22 µH inductance of the SLF10145T-220M1R9-PF is within the ±20% tolerance of the CTX25-1P-R parallel configuration (25.4 µH). However, the shielded construction differs from the unshielded CTX25-1P-R. Applications requiring unshielded operation or specific EMI characteristics must be evaluated individually. The "Not For New Designs" status of the SLF10145T-220M1R9-PF restricts its use to replacement or legacy applications.

Q: What is the significance of the ±20% tolerance specification?

A: The ±20% tolerance indicates that the actual inductance value may vary from the nominal specification within this range. For the CTX25-1P-R parallel configuration at 25.4 µH, acceptable values range from 20.32 µH to 30.48 µH. The SLF10145T-220M1R9-PF at 22 µH falls within this acceptable range, making it electrically compatible for parallel configuration applications.

Q: How do shielded and unshielded inductors differ in application performance?

A: Shielded inductors, such as the SLF10145T-220M1R9-PF, contain ferrite or other magnetic materials that confine the magnetic field, reducing electromagnetic interference (EMI) radiation to surrounding circuits. Unshielded inductors, such as the CTX25-1P-R, allow the magnetic field to extend into the surrounding space. Shielded construction typically results in lower Q factor and higher DCR but provides EMI benefits. Selection depends on circuit layout, noise sensitivity, and EMI requirements.

Q: Why is the current rating of the SLF10145T-220M1R9-PF (1.9 A) higher than the CTX25-1P-R parallel rating (960 mA)?

A: The SLF10145T-220M1R9-PF is a single inductor with 1.9 A rating, while the CTX25-1P-R is a 2-coil array with parallel and series configurations. The parallel configuration of the CTX25-1P-R achieves 960 mA through the combined characteristics of two coils. The higher current rating of the substitute indicates superior current-handling capability, making it suitable for applications requiring higher current levels.

Q: What does "Not For New Designs" mean for the SLF10145T-220M1R9-PF?

A: "Not For New Designs" indicates that the manufacturer (TDK) is not actively promoting this part for new product development. The part remains available for replacement, legacy support, and existing applications but should not be selected for new designs when alternatives exist. The CTX25-1P-R, with Active status, is the recommended choice for new product development.

Q: Are there package compatibility issues between the CTX25-1P-R and SLF10145T-220M1R9-PF?

A: Both parts use nonstandard packages and are surface mount components. The CTX25-1P-R measures 11.43mm x 11.43mm x 4.19mm, while the SLF10145T-220M1R9-PF measures 10.10mm x 10.10mm x 4.80mm. The SLF10145T-220M1R9-PF has a smaller footprint, which may be advantageous for space-constrained designs. PCB layout modifications may be required if substituting between these parts, as the footprint dimensions differ.

Q: Do both parts meet the same environmental and compliance standards?

A: Both the CTX25-1P-R and SLF10145T-220M1R9-PF are ROHS3 compliant and carry MSL 1 (Unlimited) moisture sensitivity ratings. Both support operating temperatures from -40°C, with the SLF10145T-220M1R9-PF extending to 105°C compared to the CTX25-1P-R at 85°C. For applications within the -40°C to 85°C range, both parts satisfy identical compliance requirements.