SPD74-683M Equivalent & Substitute Parts Reference

Part Overview

The SPD74-683M is a 68 µH shielded drum core wirewound inductor manufactured by API Delevan Inc., rated for 1.05 A maximum current with 380 mOhm DC resistance. This component is classified as obsolete, necessitating identification of active equivalent parts for ongoing production and maintenance applications. The SPD74-683M operates across the temperature range of -55°C to 125°C and is packaged in a nonstandard surface mount configuration.

Due to its obsolete status, substitute parts from active product lines are required to maintain design continuity and ensure component availability for new builds and field replacements.

Substiute Parts

SPD74-683M

API Delevan Inc.In Stock: 842SPD74-683M Datasheet

Current PartRFQ

HRSPD74-683M

API Delevan Inc.In Stock: 791HRSPD74-683M Datasheet

SimilarRFQ

SCRH74-680

Signal TransformerIn Stock: 966SCRH74-680 Datasheet

SimilarRFQ

SCRH74B-680

Signal TransformerIn Stock: 984SCRH74B-680 Datasheet

SimilarRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the SPD74-683M is determined by the following critical parameters:

Primary Matching Criteria:

• Inductance value: 68 µH (exact match required)
• Inductance tolerance: ±20% (must be equivalent or tighter)
• Shielding: Shielded configuration (mandatory for EMI performance)
• Mounting type: Surface mount (nonstandard package)
• Core material: Ferrite (electrical performance baseline)

Secondary Compatibility Factors:

• Current rating: Substitute must support minimum 1.05 A or higher
• DC resistance: Substitute must not exceed 380 mOhm maximum
• Operating temperature: Substitute range must encompass or exceed -55°C to 125°C
• Physical dimensions: Nonstandard package compatibility with PCB layout

All identified substitute parts maintain the 68 µH inductance specification with ±20% tolerance and ferrite core construction. Substitutes are selected from active product lines to ensure long-term availability.

Parameter Comparison

Engineering Selection Recommendations

HRSPD74-683M (API Delevan Inc.)

The HRSPD74-683M is an active product from the same manufacturer as the original SPD74-683M. This part maintains identical inductance (68 µH) and tolerance (±20%) specifications. The HRSPD74-683M features improved DC resistance (350 mOhm versus 380 mOhm maximum) and extended upper operating temperature to 130°C. However, the current rating is reduced to 650 mA, which is below the original 1.05 A specification. This substitute is suitable for applications where current demand does not exceed 650 mA. The part is available in Tape & Reel packaging and remains RoHS non-compliant.

SCRH74-680 (Signal Transformer)

The SCRH74-680 maintains the full 68 µH inductance and ±20% tolerance with 690 mA current rating and 380 mOhm maximum DC resistance matching the original specification. This part is ROHS3 compliant and available in Tape & Reel packaging. Operating temperature range is -40°C to 125°C, which covers the upper portion of the original range but does not extend to -55°C. The SCRH74-680 is suitable for applications operating above -40°C where RoHS compliance is required.

SCRH74B-680 (Signal Transformer)

The SCRH74B-680 is electrically identical to the SCRH74-680, with 68 µH inductance, 690 mA current rating, and 380 mOhm maximum DC resistance. This part is ROHS3 compliant and available in Tape & Reel packaging. Operating temperature range is -40°C to 125°C. The SCRH74B-680 differs from SCRH74-680 only in series designation and represents an alternative from the same manufacturer with identical electrical performance.

Selection Basis:

• For applications requiring full -55°C to 125°C temperature range with current ≤ 650 mA: HRSPD74-683M
• For applications operating ≥ -40°C with RoHS3 compliance requirement: SCRH74-680 or SCRH74B-680
• For applications requiring 1.05 A current rating: No direct substitute available; design review required

Frequently Asked Questions (FAQ)

Q: Can the HRSPD74-683M replace the SPD74-683M in all applications?

A: The HRSPD74-683M is suitable only for applications where the maximum current requirement does not exceed 650 mA. The original SPD74-683M is rated for 1.05 A. If your circuit requires the full 1.05 A current capacity, the HRSPD74-683M is not a direct substitute.

Q: What is the difference between SCRH74-680 and SCRH74B-680?

A: Both parts are electrically identical with 68 µH inductance, 690 mA current rating, and 380 mOhm maximum DC resistance. The difference is in the series designation (SCRH74 versus SCRH74B). Both are ROHS3 compliant and available in Tape & Reel packaging. Selection between these two parts depends on your supplier's inventory and part availability.

Q: Why does the SCRH74-680 have a different minimum operating temperature than the original SPD74-683M?

A: The SCRH74-680 operates from -40°C to 125°C, while the SPD74-683M operates from -55°C to 125°C. If your application requires operation below -40°C, the SCRH74-680 is not suitable. In this case, the HRSPD74-683M, which operates to -55°C, is the appropriate substitute if current requirements permit.

Q: Are all substitute parts available in the same package as the original SPD74-683M?

A: All substitute parts use nonstandard surface mount packages compatible with the original SPD74-683M footprint. However, physical dimensions vary slightly. The SPD74-683M measures 0.287" × 0.287" × 0.185" (height), while HRSPD74-683M measures 0.290" × 0.290" × 0.198", and SCRH74-680/SCRH74B-680 measure 0.307" × 0.307" × 0.177". Verify PCB layout compatibility before substitution.

Q: What is the significance of RoHS compliance for these parts?

A: The original SPD74-683M and HRSPD74-683M are RoHS non-compliant. The SCRH74-680 and SCRH74B-680 are ROHS3 compliant. If your application or regulatory requirements mandate RoHS compliance, only the Signal Transformer parts (SCRH74-680 or SCRH74B-680) are acceptable substitutes.

Q: Can I use SCRH74-680 in place of SPD74-683M if my circuit operates at -50°C?

A: No. The SCRH74-680 minimum operating temperature is -40°C. Operation at -50°C exceeds the specified range and is not supported. For -50°C operation, the HRSPD74-683M (rated to -55°C) is required, provided current demand does not exceed 650 mA.