SPD127R-393M Equivalent & Substitute Parts

Part Overview

The SPD127R-393M is a 39 µH shielded drum core wirewound inductor manufactured by API Delevan Inc., designed for surface mount applications requiring moderate current handling and low DC resistance. This component operates across the industrial temperature range of -55°C to 125°C and maintains active product status with full RoHS3 compliance.

Substitute parts become necessary when primary inventory is unavailable, when design requirements permit tolerance or performance variations within acceptable engineering margins, or when alternative suppliers offer equivalent functional performance with improved lead times or cost structure.

Substiute Parts

SPD127R-393M

API Delevan Inc.In Stock: 1007SPD127R-393M Datasheet

Current PartRFQ

SRR1208-390YL

Bourns Inc.In Stock: 2518SRR1208-390YL Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SPD127R-393M is evaluated based on the following critical parameters:

Inductance Value: The 39 µH specification is non-negotiable. All substitute parts must deliver this exact inductance at the 1 kHz test frequency.

Current Handling: The main part specifies 2.8 A continuous current rating. Substitute parts must support at least this current level to ensure equivalent thermal performance and prevent premature saturation in the application circuit.

DC Resistance: The 80 mOhm maximum DCR establishes the acceptable power loss profile. Substitutes with lower DCR values improve efficiency and reduce thermal stress.

Inductance Tolerance: The ±20% tolerance defines the acceptable inductance variation. Substitutes with tighter tolerances (such as ±15%) provide improved circuit performance without requiring design modification.

Core Material and Shielding: Ferrite core construction with shielding is mandatory for EMI performance and frequency response characteristics. Both attributes must be preserved in any substitute.

Mounting and Package: Surface mount configuration is required for PCB assembly compatibility. Physical dimensions must accommodate the target PCB layout.

Regulatory Compliance: RoHS3 compliance and REACH unaffected status are non-negotiable for regulated applications.

Operating Temperature: The -55°C to 125°C range must be met or exceeded to ensure reliability across all deployment environments.

Parameter Comparison

Engineering Selection Recommendations

Primary Selection (SPD127R-393M): Use when API Delevan supply is available and the full -55°C to 125°C operating range is required. This part offers the specified 2.8 A continuous current rating and 80 mOhm maximum DCR.

Substitute Selection (SRR1208-390YL): Use when Bourns supply is available and the following conditions are met:

1. Application operating temperature does not require operation below -40°C
2. Continuous current requirement does not exceed 2.5 A
3. PCB layout accommodates the slightly larger footprint (12.70mm x 12.70mm) and increased height (8.50mm)
4. The improved saturation current (3.4 A) and lower DCR (76 mOhm) provide performance benefits

Both parts maintain active product status, full RoHS3 compliance, and REACH unaffected designation, ensuring regulatory compatibility for current and future applications.

Frequently Asked Questions (FAQ)

Q: Can SRR1208-390YL replace SPD127R-393M in all applications?

A: No. The substitute is suitable only when continuous current requirements do not exceed 2.5 A and minimum operating temperature is -40°C or higher. Verify these conditions against your circuit requirements before substitution.

Q: What is the impact of the 0.3 A lower current rating on the substitute?

A: The SRR1208-390YL is rated for 2.5 A continuous current versus 2.8 A for the main part. If your application requires sustained current above 2.5 A, the substitute will experience higher thermal stress and reduced component life. The substitute's higher saturation current (3.4 A) provides some margin but does not extend the continuous rating.

Q: Does the tighter tolerance (±15% vs ±20%) on the substitute affect compatibility?

A: No. Tighter tolerance is a performance improvement. The substitute's ±15% tolerance is a subset of the main part's ±20% tolerance range, ensuring equivalent or better inductance accuracy.

Q: Are the physical dimension differences significant?

A: Yes. The substitute is 0.7mm larger in length and width (12.70mm vs 12.00mm) and 0.5mm taller (8.50mm vs 8.00mm). Verify that your PCB layout provides adequate clearance for these dimensions before substitution.

Q: What is the significance of the lower DC resistance in the substitute?

A: Lower DCR (76 mOhm vs 80 mOhm) reduces power dissipation and heat generation. This is a performance benefit that improves efficiency and thermal performance, with no negative impact on circuit function.

Q: Are both parts suitable for RoHS3 and REACH-regulated applications?

A: Yes. Both SPD127R-393M and SRR1208-390YL are ROHS3 compliant and REACH unaffected, meeting regulatory requirements for current and future applications.

Q: What is the difference in self-resonant frequency between the parts?

A: The substitute specifies a self-resonant frequency of 6 MHz, while the main part does not provide this specification. For high-frequency applications, the substitute's defined SRF may provide additional design confidence.